Duckbill dinosaurs

The unarmored, hadrosaurian dinosaurs of the late Cretaceous of North America constitute an interesting group about which much has been written and many species described. A review of this literature showed many different angles of approach, and it was in part to reconcile these various descriptions and reduce them to certain comparable common factors that this monographic study was undertaken. Aside from the mere compilation of the literature of these dinosaurs, redescriptions were prepared, nearly always in the presence of the original types and such other associated material as had come to light since the species was named.

@incollection{doi101130spe40p1,
    author = "Lull, R. S. and Wright, Nelda E.",
    title = "Hadrosaurian Dinosaurs of North America",
    year = "1942",
    booktitle = "Geological Society of America Special Papers",
    abstract = "The unarmored, hadrosaurian dinosaurs of the late Cretaceous of North America constitute an interesting group about which much has been written and many species described. A review of this literature showed many different angles of approach, and it was in part to reconcile these various descriptions and reduce them to certain comparable common factors that this monographic study was undertaken. Aside from the mere compilation of the literature of these dinosaurs, redescriptions were prepared, nearly always in the presence of the original types and such other associated material as had come to light since the species was named.",
    url = "https://doi.org/10.1130/spe40-p1",
    doi = "10.1130/spe40-p1",
    openalex = "W1879508526"
}

Twenty-six new species of Foraminifera were obtained from the Upper Triassic of northern Alaska. This is the first record of Triassic Foraminifera in the western hemisphere. Eighteen genera are represented, one of them new, and there are nine families. Twelve species belong to the family Lagenidae, five to the Polymorphinidae, two each to the Trochamminidae and Lituolidae, and one each to the Ammodiscidae, Verneuilinidae, Buliminidae, Spirillinidae, and Rotaliidae. It is thus a more varied fauna than any previously described from the Triassic. The specimens are better preserved than Triassic Foraminifera known heretofore.

@book{openalexw2131708958,
    author = "Tappan, Helen",
    title = "Foraminifera From the Arctic Slope of Alaska",
    year = "1962",
    booktitle = "U.S. Gov. Print. Off. eBooks",
    abstract = "Twenty-six new species of Foraminifera were obtained from the Upper Triassic of northern Alaska. This is the first record of Triassic Foraminifera in the western hemisphere. Eighteen genera are represented, one of them new, and there are nine families. Twelve species belong to the family Lagenidae, five to the Polymorphinidae, two each to the Trochamminidae and Lituolidae, and one each to the Ammodiscidae, Verneuilinidae, Buliminidae, Spirillinidae, and Rotaliidae. It is thus a more varied fauna than any previously described from the Triassic. The specimens are better preserved than Triassic Foraminifera known heretofore.",
    openalex = "W2131708958"
}

The Late Cretaceous Oldman Formation comprises sediments that were deposited along the margin of a great inland sea that covered much of the western interior of North America. The environment of deposition appears to have been tracts of fluvial marshes that separated “islands” of higher, drier ground. The climate was probably warm—temperate, and it is suggested that upland plant communities were parkland—like in aspect. The large dinosaurs of this community comprised animals that were between a hippopotamus and a large African elephant in adult weight. Some workers have suggested that dinosaurs had metabolic rates comparable to those of living birds or mammals. By extrapolating from the food consumption rates of these living endotherms it is possible to obtain crude estimates of the ingestion rates of endothermic dinosaurs. Similar extrapolations from the ingestion rates of living reptiles and amphibians provide estimates of the ingestion rates of ectothermic dinosaurs. By deriving an empirical equation relating the ratio of annual secondary productivity/average annual biomass to adult weight in living mammals, and employing estimates of adult weight and biomass for the herbivorous dinosaur populations, it is possible to estimate the annual secondary production of endothermic Oldman herbivorous dinosaurs. If the body weight vs. production/biomass relation derived for mammals can be applied to ectothermic tetrapods, it is possible to estimate annual secondary production of ectothermic dinosaur populations. These calculations suggest that the annual secondary production of endothermic herbivorous dinosaurs would have been insufficient to meet the food requirements of an endothermic carnivorous dinosaur population as large as is preserved in the Oldman Formation. However, ectothermic carnivorous dinosaurs would have been easily able to make energetic ends meet. Unfortunately, the situation is complicated by the possibility that carnivores are overrepresented in collection from the Oldman. Because of this, I cannot presently decide between ectothermy and endothermy in dinosaurs on the basis of methods presented in this paper. Alternative methods that may be more successful in this regard are discussed. It is hoped that as paleontologists collect fossils from an ecological point of view the methods presented in this paper can be employed to make realistic statements about the trophic dynamics of ancient vertebrate communities.

@article{doi1023071941052,
    author = "Farlow, James O.",
    title = "A Consideration of the Trophic Dynamics of a Late Cretaceous Large‐Dinosaur Community (Oldman Formation)",
    year = "1976",
    journal = "Ecology",
    abstract = "The Late Cretaceous Oldman Formation comprises sediments that were deposited along the margin of a great inland sea that covered much of the western interior of North America. The environment of deposition appears to have been tracts of fluvial marshes that separated “islands” of higher, drier ground. The climate was probably warm—temperate, and it is suggested that upland plant communities were parkland—like in aspect. The large dinosaurs of this community comprised animals that were between a hippopotamus and a large African elephant in adult weight. Some workers have suggested that dinosaurs had metabolic rates comparable to those of living birds or mammals. By extrapolating from the food consumption rates of these living endotherms it is possible to obtain crude estimates of the ingestion rates of endothermic dinosaurs. Similar extrapolations from the ingestion rates of living reptiles and amphibians provide estimates of the ingestion rates of ectothermic dinosaurs. By deriving an empirical equation relating the ratio of annual secondary productivity/average annual biomass to adult weight in living mammals, and employing estimates of adult weight and biomass for the herbivorous dinosaur populations, it is possible to estimate the annual secondary production of endothermic Oldman herbivorous dinosaurs. If the body weight vs. production/biomass relation derived for mammals can be applied to ectothermic tetrapods, it is possible to estimate annual secondary production of ectothermic dinosaur populations. These calculations suggest that the annual secondary production of endothermic herbivorous dinosaurs would have been insufficient to meet the food requirements of an endothermic carnivorous dinosaur population as large as is preserved in the Oldman Formation. However, ectothermic carnivorous dinosaurs would have been easily able to make energetic ends meet. Unfortunately, the situation is complicated by the possibility that carnivores are overrepresented in collection from the Oldman. Because of this, I cannot presently decide between ectothermy and endothermy in dinosaurs on the basis of methods presented in this paper. Alternative methods that may be more successful in this regard are discussed. It is hoped that as paleontologists collect fossils from an ecological point of view the methods presented in this paper can be employed to make realistic statements about the trophic dynamics of ancient vertebrate communities.",
    url = "https://doi.org/10.2307/1941052",
    doi = "10.2307/1941052",
    openalex = "W2050538558",
    references = "doi101111j155856461974tb00777x, doi102475ajs2628975"
}

@article{doi101007bf02988144,
    author = "Galton, Peter M.",
    title = "Dryosaurus, a hypsilophodontid dinosaur from the upper jurassic of north America and Africa postcranial skeleton",
    year = "1981",
    journal = "Paläontologische Zeitschrift",
    url = "https://doi.org/10.1007/bf02988144",
    doi = "10.1007/bf02988144",
    openalex = "W2027448836",
    references = "doi101017s009483730000676x, doi101130spe40p1, doi1023071292217, doi1023071440541, doi102475ajss31484514, doi102475ajss31695411, doi102475ajss319111253, doi102475ajss327158161, doi105479si00963801361666197, doi105962bhltitle60562, doi105962p313819, openalexw3208547338, owen2015monograph"
}

ABSTRACT Forty oil samples from across the North Slope of Alaska have been analyzed by the U.S. Bureau of Mines and the U.S. Geological Survey. Results of these analyses suggest two separate genetic oil types. The first, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and includes oil from seeps in the Skull Cliff, Cape Simpson, Manning Point, and Ungoon Point areas, and oils from Wolf Creek test 3, and the Cape Simpson and Umiat oil fields. These are higher gravity, low-sulfur oils with no, or slight, odd-numbered n-alkane predominance and pristane to phytane ratios greater than 1.5. Also, these oils have δ13C values ranging from −29.1 to −27.8 parts per thousand (ppt) and δ34S values from −10.3 to −4.9 ppt. The second type, the Barrow-Prudhoe oil type, occurs in reservoir rocks of Carboniferous to Cretaceous age and includes oils from South Barrow gas field, Prudhoe Bay oil field, and the Fish Creek test well 1. Physical properties of Barrow-Prudhoe oils are variable, but in general the oils are medium-gravity, high-sulfur oils with slight even-numbered n-alkane predominance and pristane to phytane ratios less than 1.5. Also these oils have δ13C values of −30.3 to −29.8 ppt and δ34S values from −3.0 to +2.1 ppt. The two types are believed to originate from different source rocks; the Barrow-Prudhoe type may have originated from a carbonate or other iron-deficient source rock, and the Simpson-Umiat type from a siliciclastic source rock. Occurrences of the two oil types, when outlined on a map, indicate at least two areas for additional exploration: for the Barrow-Prudhoe type, in stratigraphic traps along and adjacent to the Barrow arch, and for the Simpson-Umiat type, in Cretaceous rocks along the trend between the Simpson and Umiat oil fields and in Cretaceous and Tertiary rocks from Prudhoe Bay field to the William O. Douglas Arctic Wildlife Range.

@article{doi1013062f91999f16ce11d78645000102c1865d,
    author = "Magoon, Leslie B. and Claypool, George E.",
    title = "Two Oil Types on North Slope of Alaska—Implications for Exploration",
    year = "1981",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Forty oil samples from across the North Slope of Alaska have been analyzed by the U.S. Bureau of Mines and the U.S. Geological Survey. Results of these analyses suggest two separate genetic oil types. The first, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and includes oil from seeps in the Skull Cliff, Cape Simpson, Manning Point, and Ungoon Point areas, and oils from Wolf Creek test 3, and the Cape Simpson and Umiat oil fields. These are higher gravity, low-sulfur oils with no, or slight, odd-numbered n-alkane predominance and pristane to phytane ratios greater than 1.5. Also, these oils have δ13C values ranging from −29.1 to −27.8 parts per thousand (ppt) and δ34S values from −10.3 to −4.9 ppt. The second type, the Barrow-Prudhoe oil type, occurs in reservoir rocks of Carboniferous to Cretaceous age and includes oils from South Barrow gas field, Prudhoe Bay oil field, and the Fish Creek test well 1. Physical properties of Barrow-Prudhoe oils are variable, but in general the oils are medium-gravity, high-sulfur oils with slight even-numbered n-alkane predominance and pristane to phytane ratios less than 1.5. Also these oils have δ13C values of −30.3 to −29.8 ppt and δ34S values from −3.0 to +2.1 ppt. The two types are believed to originate from different source rocks; the Barrow-Prudhoe type may have originated from a carbonate or other iron-deficient source rock, and the Simpson-Umiat type from a siliciclastic source rock. Occurrences of the two oil types, when outlined on a map, indicate at least two areas for additional exploration: for the Barrow-Prudhoe type, in stratigraphic traps along and adjacent to the Barrow arch, and for the Simpson-Umiat type, in Cretaceous rocks along the trend between the Simpson and Umiat oil fields and in Cretaceous and Tertiary rocks from Prudhoe Bay field to the William O. Douglas Arctic Wildlife Range.",
    url = "https://doi.org/10.1306/2f91999f-16ce-11d7-8645000102c1865d",
    doi = "10.1306/2f91999f-16ce-11d7-8645000102c1865d",
    openalex = "W2139401489"
}

ABSTRACT The sequence of rocks described lies primarily in the DeLong and Endicott Mountains in the western and central parts of the Brooks Range, northern Alaska. New names are given to dominantly siliceous and shaly sedimentary rocks of Mississippian through early Middle Jurassic age. The Kuna Formation (new name) consists dominantly of black bedded chert, shale, limestone, and dolomite within the Lisburne Group; some beds are phosphatic, and mafic extrusive igneous rocks occur in a few areas. Paleontologic data suggest an Early Mississippian to Early or Middle Pennsyl-vanian age for the Kuna Formation. Because the formation intertongues eastward with light-colored shallow-water carbonate rocks of the Wachsmuth and Alapah Limestones of the Lisburne Group, it is also assigned to the Lisburne Group. Light-colored shallow-water carbonate rocks of other formations of the Lisburne Group were apparently also deposited on the south, but have been telescoped northward by thrust faulting over the darker Kuna Formation. The formation ranges up to 100 m in thickness. The Etivluk Group (new name) is composed of dominantly siliceous beds of the previously named Siksikpuk Formation and overlying Otuk Formation (new name). New paleontologic data suggest that the Siksikpuk is of Pennsylvanian, Permian, and Early Triassic age. The Otuk Formation consists of up to 100 m rhythmically interbedded chert, silicified limestone, and shale previously assigned in this area to the Shublik Formation. A thin but distinctive zone of early Middle Jurassic organic shale and dolomitic limestone locally present within the top of the Otuk constitutes the Blankenship Member (new name), which is up to 7 m thick. Paleontologic data indicate that the Otuk Formation ranges in age from late Early Triassic to early Middle Jurassic. These dominantly siliceous stratigraphic units appear to be limited to the allochthons of the western and central Brooks Range; they are not known to be present on the autochthonous complex of the northeastern Brooks Range and subsurface Arctic Slope.

@article{doi10130603b59b0c16d111d78645000102c1865d,
    author = "Mull, I. L. Tailleur C. G. and Tailleur, I. L. and Mayfield, C. F. and Ellersieck, Inyo and Curtis, S.",
    title = "New Upper Paleozoic and Lower Mesozoic Stratigraphic Units, Central and Western Brooks Range, Alaska",
    year = "1982",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT The sequence of rocks described lies primarily in the DeLong and Endicott Mountains in the western and central parts of the Brooks Range, northern Alaska. New names are given to dominantly siliceous and shaly sedimentary rocks of Mississippian through early Middle Jurassic age. The Kuna Formation (new name) consists dominantly of black bedded chert, shale, limestone, and dolomite within the Lisburne Group; some beds are phosphatic, and mafic extrusive igneous rocks occur in a few areas. Paleontologic data suggest an Early Mississippian to Early or Middle Pennsyl-vanian age for the Kuna Formation. Because the formation intertongues eastward with light-colored shallow-water carbonate rocks of the Wachsmuth and Alapah Limestones of the Lisburne Group, it is also assigned to the Lisburne Group. Light-colored shallow-water carbonate rocks of other formations of the Lisburne Group were apparently also deposited on the south, but have been telescoped northward by thrust faulting over the darker Kuna Formation. The formation ranges up to 100 m in thickness. The Etivluk Group (new name) is composed of dominantly siliceous beds of the previously named Siksikpuk Formation and overlying Otuk Formation (new name). New paleontologic data suggest that the Siksikpuk is of Pennsylvanian, Permian, and Early Triassic age. The Otuk Formation consists of up to 100 m rhythmically interbedded chert, silicified limestone, and shale previously assigned in this area to the Shublik Formation. A thin but distinctive zone of early Middle Jurassic organic shale and dolomitic limestone locally present within the top of the Otuk constitutes the Blankenship Member (new name), which is up to 7 m thick. Paleontologic data indicate that the Otuk Formation ranges in age from late Early Triassic to early Middle Jurassic. These dominantly siliceous stratigraphic units appear to be limited to the allochthons of the western and central Brooks Range; they are not known to be present on the autochthonous complex of the northeastern Brooks Range and subsurface Arctic Slope.",
    url = "https://doi.org/10.1306/03b59b0c-16d1-11d7-8645000102c1865d",
    doi = "10.1306/03b59b0c-16d1-11d7-8645000102c1865d",
    openalex = "W2145351712"
}

ABSTRACT Analysis of depositional environments, new paleontologic data, and analogy with depositional patterns observed in areas to the west all indicate the need for revision of Cretaceous and lower Tertiary stratigraphy in northeastern Alaska. In the Sadlerochit Mountains area of the Arctic National Wildlife Refuge, the northern-derived (Ellesmerian), late Neocomian Kemik Sandstone Member and organic-rich pebble shale member of the Kongakut Formation unconformably overlie Jurassic and Triassic rocks. The unconformity, which is of mid-Neocomian age, is present throughout northernmost Alaska and passes southward into a conformable shelf sequence. After pebble shale deposition, the depositional pattern is simply one of progradational basin filling from a southern (Brookian) provenance. This pattern is represented in vertical sequence initially by deep-marine basinal deposits succeeded by prodelta slope shales, and ultimately by deltaic deposits that prograded to the east or northeast in a predictable fashion over most of the area. The better known, thick, shallow-marine and nonmarine units in the central North Slope grade to thin prodelta or basinal turbidites; some units are entirely missing owing to nondeposition on the south-dipping flank of the basin. No evidence exists for subaerial erosion to explain these marked stratigraphic changes. In the Sadlerochit Mountains area, which may be an extension of the Barrow arch, the pebble shale (Neocomian) is overlain by about 1,600 ft (500 m) of deep-water deposits of Late Cretaceous age; Aptian and Albian rocks are either absent (by nondeposition) or are represented by a thin, condensed section. Here the Upper Cretaceous to lower Tertiary section consists of basinal shale, bentonite, and thin-bedded prodelta turbidites. Two noteworthy features in this sequence are an interval of organic-rich shale of probable Turonian to Coniacian age just above the pebble shale, and the placement of the Cretaceous-Tertiary boundary within deep-marine deposits. Unlike the western part of the North Slope, where deltaic deposition occurred in the Early Cretaceous, prograding deltaic deposition did not reach the western part of the Wildlife Refuge until early in the Tertiary. The consistent pattern of easterly deltaic progradation is complicated at Igilatvik (Sabbath) Creek (in the north-central Wildlife Refuge) by the occurrence of thick, regressive, dominantly nonmarine deposits of early Tertiary age, which apparently prograded into the basin from the south or southeast.

@article{doi10130603b5b6ff16d111d78645000102c1865d,
    author = "Molenaar, C. M.",
    title = "Depositional Relations of Cretaceous and Lower Tertiary Rocks, Northeastern Alaska",
    year = "1983",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Analysis of depositional environments, new paleontologic data, and analogy with depositional patterns observed in areas to the west all indicate the need for revision of Cretaceous and lower Tertiary stratigraphy in northeastern Alaska. In the Sadlerochit Mountains area of the Arctic National Wildlife Refuge, the northern-derived (Ellesmerian), late Neocomian Kemik Sandstone Member and organic-rich pebble shale member of the Kongakut Formation unconformably overlie Jurassic and Triassic rocks. The unconformity, which is of mid-Neocomian age, is present throughout northernmost Alaska and passes southward into a conformable shelf sequence. After pebble shale deposition, the depositional pattern is simply one of progradational basin filling from a southern (Brookian) provenance. This pattern is represented in vertical sequence initially by deep-marine basinal deposits succeeded by prodelta slope shales, and ultimately by deltaic deposits that prograded to the east or northeast in a predictable fashion over most of the area. The better known, thick, shallow-marine and nonmarine units in the central North Slope grade to thin prodelta or basinal turbidites; some units are entirely missing owing to nondeposition on the south-dipping flank of the basin. No evidence exists for subaerial erosion to explain these marked stratigraphic changes. In the Sadlerochit Mountains area, which may be an extension of the Barrow arch, the pebble shale (Neocomian) is overlain by about 1,600 ft (500 m) of deep-water deposits of Late Cretaceous age; Aptian and Albian rocks are either absent (by nondeposition) or are represented by a thin, condensed section. Here the Upper Cretaceous to lower Tertiary section consists of basinal shale, bentonite, and thin-bedded prodelta turbidites. Two noteworthy features in this sequence are an interval of organic-rich shale of probable Turonian to Coniacian age just above the pebble shale, and the placement of the Cretaceous-Tertiary boundary within deep-marine deposits. Unlike the western part of the North Slope, where deltaic deposition occurred in the Early Cretaceous, prograding deltaic deposition did not reach the western part of the Wildlife Refuge until early in the Tertiary. The consistent pattern of easterly deltaic progradation is complicated at Igilatvik (Sabbath) Creek (in the north-central Wildlife Refuge) by the occurrence of thick, regressive, dominantly nonmarine deposits of early Tertiary age, which apparently prograded into the basin from the south or southeast.",
    url = "https://doi.org/10.1306/03b5b6ff-16d1-11d7-8645000102c1865d",
    doi = "10.1306/03b5b6ff-16d1-11d7-8645000102c1865d",
    openalex = "W2001197856"
}

Abstract Fossil dinosaur skin impressions and tracks and fossil wood were collected in 1978 from the Cretaceous Corwin Formation during field investigations of coal deposits in the National Petroleum Reserve on the North Slope of Alaska. The fossils were discovered in sandstones in cutbanks of the Kokolik River and its tributaries, 315 kilometers north of the Arctic Circle. They occur in an ancient, river-dominated, bird-foot delta system that extends from near the north edge of the Brooks Range northward across the Arctic Coastal Plain and for distances under the Chukchi Sea. The fossils provide limited evidence for a warm, temperate to subtropical climate and a swampy, forested landscape for northern Alaska between 100 million and 70 million years ago.

@article{openalexw2204429280,
    author = "Roehler, Henry W. and Stricker, Gary D.",
    title = "Dinosaur and Wood Fossils from the Cretaceous Corwin Formation in the National Petroleum Reserve, North Slope of Alaska",
    year = "1984",
    abstract = "Abstract Fossil dinosaur skin impressions and tracks and fossil wood were collected in 1978 from the Cretaceous Corwin Formation during field investigations of coal deposits in the National Petroleum Reserve on the North Slope of Alaska. The fossils were discovered in sandstones in cutbanks of the Kokolik River and its tributaries, 315 kilometers north of the Arctic Circle. They occur in an ancient, river-dominated, bird-foot delta system that extends from near the north edge of the Brooks Range northward across the Arctic Coastal Plain and for distances under the Chukchi Sea. The fossils provide limited evidence for a warm, temperate to subtropical climate and a swampy, forested landscape for northern Alaska between 100 million and 70 million years ago.",
    openalex = "W2204429280"
}

@misc{smith1984petroleum,
    author = "Smith, T. N.",
    title = "Petroleum development, North Slope of Alaska",
    year = "1984",
    url = "https://doi.org/10.14509/739",
    doi = "10.14509/739"
}

@incollection{crossref1985petroleum,
    title = "Petroleum Geochemistry of North Slope Alaska",
    year = "1985",
    booktitle = "Alaska North Slope Oil-Rock Correlation Study",
    url = "https://doi.org/10.1306/st20445c12",
    doi = "10.1306/st20445c12",
    pages = "243-279"
}

A 14-m-thick section of marine and nonmarine sediments of the Gubik Formation of northern Alaska, exposed in bluffs near Ocean Point on the Colville River, has been studied by means of pollen analysis. Pollen from the marine sediments, of probable late Pliocene age, records a boreal forest of spruce and birch with minor amounts of alder in the adjacent terrestrial vegetation. Pine and perhaps true fir were probably at or near their northern limit here, but hemlocks and hardwoods were absent. The suggested environment for the Arctic Slope during the time represented by the marine sediments is similar to that of present-day Anchorage. Pollen floras from the overlying fluvial strata, of early or middle Pleistocene age, record predominantly herbaceous taxa indicating tundra conditions probably more severe than those of the present day. These deposits were most likely contemporaneous with glacial conditions in the Brooks Range to the south. Pollen of woody taxa (spruce, alder, birch, heaths) is rare through most of the section, although birch and alder percentages similar to those found in modern river sediments indicate an interstadial or interglacial warming in midsection. Inland climates during glacial episodes may have been similar to those of the present Arctic coast.

@article{doi1010160033589485900523,
    author = "Nelson, Robert E. and Carter, L. David",
    title = "Pollen Analysis of a Late Pliocene and Early Pleistocene Section from the Gubik Formation of Arctic Alaska",
    year = "1985",
    journal = "Quaternary Research",
    abstract = "A 14-m-thick section of marine and nonmarine sediments of the Gubik Formation of northern Alaska, exposed in bluffs near Ocean Point on the Colville River, has been studied by means of pollen analysis. Pollen from the marine sediments, of probable late Pliocene age, records a boreal forest of spruce and birch with minor amounts of alder in the adjacent terrestrial vegetation. Pine and perhaps true fir were probably at or near their northern limit here, but hemlocks and hardwoods were absent. The suggested environment for the Arctic Slope during the time represented by the marine sediments is similar to that of present-day Anchorage. Pollen floras from the overlying fluvial strata, of early or middle Pleistocene age, record predominantly herbaceous taxa indicating tundra conditions probably more severe than those of the present day. These deposits were most likely contemporaneous with glacial conditions in the Brooks Range to the south. Pollen of woody taxa (spruce, alder, birch, heaths) is rare through most of the section, although birch and alder percentages similar to those found in modern river sediments indicate an interstadial or interglacial warming in midsection. Inland climates during glacial episodes may have been similar to those of the present Arctic coast.",
    url = "https://doi.org/10.1016/0033-5894(85)90052-3",
    doi = "10.1016/0033-5894(85)90052-3",
    openalex = "W2150993285",
    references = "doi1010800072139519769989773"
}

A discontinuous, elongate zone of mafic and ultramafic plutonic rock crops out in south-central Alaska for a distance of more than 1000 km. Intermediate- and detailed-scale geologic mapping, petrographic study, and compositional data suggest that the plutonic rocks are compositionally, petrologically, and mineralogically distinct from rocks in mid-ocean ridge and back-arc basin ophiolites. The mafic and ultramafic rocks instead represent part of the plutonic core of an intraoceanic island arc.The mafic–ultramafic zone, referred to as the Border Ranges ultramafic and mafic complex (BRUMC), is composed of ultramafic cumulates, gabbronorite cumulates, and massive gabbronorites. A very minor amount of tectonized ultramafic rock of mantle origin is present in the southern part of the BRUMC. A thick sequence of andesitic volcanic rocks, the Talkeetna Formation of Early Jurassic age, lies to the north of and structurally above the mafic–ultramafic zone. Voluminous calcalkaline plutons composed of quartz diorite, tonalite, and minor granodiorite intrude both the mafic plutonic complexes and the andesitic volcanic rocks.The cumulate ultramafic sections are largely composed of dunite ± chromite, wehrlite, clinopyroxenite, and websterite and are characterized by a wide range of Mg–Fe silicate compositions (Fo 90–81; En 45–50, Fs 1–7, Wo 45–49; En 88–82, Fs 11–17), chrome-rich spinels, and a lack of plagioclase. The gabbroic sections are composed of gabbronorites with up to 10–15% magnetite ± ilmenite. Hornblende, if present, is a very minor phase in most gabbroic rocks. The coexisting mineral compositions seen in the gabbroic rocks of the BRUMC (relatively iron-rich pyroxene—Fs 6–13, En 45–40; En 81–63 —and calcic plagioclase An 75–100) and their association with magnetite are common in plutonic xenoliths in island-arc rocks.The mineralogy and composition of the gabbroic rocks in the BRUMC are consistent with the fractional crystallization products predicted to be associated with the formation of andesite from a basaltic magma. Consideration of additional data, including detailed and regional field mapping of the plutonic and volcanic rocks and geochronology of the BRUMC and the nearby Talkeetna arc volcanic rocks, strongly suggests that the BRUMC represents relatively deep fractional crystallization products of magmas that produced the Talkeetna Formation volcanic rocks. Field relationships also indicate that intrusion of quartz diorites, tonalites, and granodiorites of batholithic proportions occurred slightly later than formation of the BRUMC.

@article{doi101139e85106,
    author = "Burns, L.E.",
    title = "The Border Ranges ultramafic and mafic complex, south-central Alaska: cumulate fractionates of island-arc volcanics",
    year = "1985",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "A discontinuous, elongate zone of mafic and ultramafic plutonic rock crops out in south-central Alaska for a distance of more than 1000 km. Intermediate- and detailed-scale geologic mapping, petrographic study, and compositional data suggest that the plutonic rocks are compositionally, petrologically, and mineralogically distinct from rocks in mid-ocean ridge and back-arc basin ophiolites. The mafic and ultramafic rocks instead represent part of the plutonic core of an intraoceanic island arc.The mafic–ultramafic zone, referred to as the Border Ranges ultramafic and mafic complex (BRUMC), is composed of ultramafic cumulates, gabbronorite cumulates, and massive gabbronorites. A very minor amount of tectonized ultramafic rock of mantle origin is present in the southern part of the BRUMC. A thick sequence of andesitic volcanic rocks, the Talkeetna Formation of Early Jurassic age, lies to the north of and structurally above the mafic–ultramafic zone. Voluminous calcalkaline plutons composed of quartz diorite, tonalite, and minor granodiorite intrude both the mafic plutonic complexes and the andesitic volcanic rocks.The cumulate ultramafic sections are largely composed of dunite ± chromite, wehrlite, clinopyroxenite, and websterite and are characterized by a wide range of Mg–Fe silicate compositions (Fo 90–81; En 45–50, Fs 1–7, Wo 45–49; En 88–82, Fs 11–17), chrome-rich spinels, and a lack of plagioclase. The gabbroic sections are composed of gabbronorites with up to 10–15\% magnetite ± ilmenite. Hornblende, if present, is a very minor phase in most gabbroic rocks. The coexisting mineral compositions seen in the gabbroic rocks of the BRUMC (relatively iron-rich pyroxene—Fs 6–13, En 45–40; En 81–63 —and calcic plagioclase An 75–100) and their association with magnetite are common in plutonic xenoliths in island-arc rocks.The mineralogy and composition of the gabbroic rocks in the BRUMC are consistent with the fractional crystallization products predicted to be associated with the formation of andesite from a basaltic magma. Consideration of additional data, including detailed and regional field mapping of the plutonic and volcanic rocks and geochronology of the BRUMC and the nearby Talkeetna arc volcanic rocks, strongly suggests that the BRUMC represents relatively deep fractional crystallization products of magmas that produced the Talkeetna Formation volcanic rocks. Field relationships also indicate that intrusion of quartz diorites, tonalites, and granodiorites of batholithic proportions occurred slightly later than formation of the BRUMC.",
    url = "https://doi.org/10.1139/e85-106",
    doi = "10.1139/e85-106",
    openalex = "W2164777462"
}

The Alaska North Slope oil-rock correlation study was organized because several oil companies requested oil and rock samples for geochemical analyses that were recovered during the exploration drilling in the National Petroleum Reserve in Alaska (NPRA). Samples acquired with public funds could not be given to private organizations unless some guarantees could be provided that the information acquired from these samples could be made available to the public. For this reason, in August 1981, we sent out over 40 invitations to research laboratories in industry, government, and academia.Requirements to participate in this study included: (1) participation in an AAPG-sponsored research conference, (2) presentation of the data interpretations at the 1983 Annual AAPG Meeting in Dallas Texas, and (3) contribution of a manuscript, to include all acquired data and interpretations, that would be included in a symposium volume. If a research group wished to participate, they were to write a letter of intent that included their proposed analytical program and a statement indicating that the requirements would be adhered to by their group. Even with these stringent requirements, 30 research groups wished to participate. A balanced cross section of research groups are participating and are as follows: 15 from oil companies, 7 from commercial laboratories, 7 from government laboratories, and 1 university laboratory. These groups are listed in Table 1.In January 1982, each research group was sent 8 oils and 15 rocks recovered from NPRA drilling and 1 oil from the Prudhoe Bay field. Each group then proceeded to analyze these samples as they indicated in their letter of intent.

@incollection{doi101306st20445c1,
    author = "Bird, Kenneth J.",
    title = "The Framework Geology of the North Slope of Alaska as Related to Oil-Source Rock Correlations",
    year = "1985",
    booktitle = "American Association of Petroleum Geologists eBooks",
    abstract = "The Alaska North Slope oil-rock correlation study was organized because several oil companies requested oil and rock samples for geochemical analyses that were recovered during the exploration drilling in the National Petroleum Reserve in Alaska (NPRA). Samples acquired with public funds could not be given to private organizations unless some guarantees could be provided that the information acquired from these samples could be made available to the public. For this reason, in August 1981, we sent out over 40 invitations to research laboratories in industry, government, and academia.Requirements to participate in this study included: (1) participation in an AAPG-sponsored research conference, (2) presentation of the data interpretations at the 1983 Annual AAPG Meeting in Dallas Texas, and (3) contribution of a manuscript, to include all acquired data and interpretations, that would be included in a symposium volume. If a research group wished to participate, they were to write a letter of intent that included their proposed analytical program and a statement indicating that the requirements would be adhered to by their group. Even with these stringent requirements, 30 research groups wished to participate. A balanced cross section of research groups are participating and are as follows: 15 from oil companies, 7 from commercial laboratories, 7 from government laboratories, and 1 university laboratory. These groups are listed in Table 1.In January 1982, each research group was sent 8 oils and 15 rocks recovered from NPRA drilling and 1 oil from the Prudhoe Bay field. Each group then proceeded to analyze these samples as they indicated in their letter of intent.",
    url = "https://doi.org/10.1306/st20445c1",
    doi = "10.1306/st20445c1",
    openalex = "W2168586266"
}

@article{mickey1985jurassicneocomian,
    author = "Mickey, M. B. and Haga, Hideyo",
    title = "Jurassic-Neocomian Biostratigraphy, North Slope, Alaska",
    year = "1985",
    journal = "AAPG Bulletin",
    url = "https://doi.org/10.1306/ad4626a0-16f7-11d7-8645000102c1865d",
    doi = "10.1306/ad4626a0-16f7-11d7-8645000102c1865d",
    number = "4",
    pages = "669-669",
    volume = "69"
}

Closely related terrestrial vertebrates in Cretaceous mid-latitude (30/sup 0/ to 50/sup 0/) faunas of North America and Asia as well as scattered occurrences of footprints and skin impressions suggested that in the Late Mesozoic the Alaskan North Slope supported a diverse fauna. In 1961 abundant skeletal elements of Cretaceous, Alaskan dinosaurs (hadrosaurids) were discovered by the late R.L. Liscomb. This material is being described by K.L. Davies. Additional fossils collected by E.M. Brouwers and her associates include skeletal elements of hadrosaurid and carnosaurian (.tyrannosaurid) dinosaurs and other vertebrates. The fossil locality on the North Slope is not at about 70/sup 0/N. In the Late Cretaceous the members of this fauna were subject to the daylight regime and environment at a paleolatitude closer to 80/sup 0/N. Current hypotheses attributing extinctions of dinosaurs and some other terrestrial vertebrates to impact of an extraterrestrial object cite periods of darkness, decreased temperature (possibly followed by extreme warming) and acid rain as the direct causes of their demise. Unless members of this North Slope fauna undertook long-distance migrations, their high latitude occurrence indicates groups of dinosaurs and other terrestrial vertebrates regularly tolerated months of darkness.

@article{s27d8bedefc50ce4561424495457a173f1e18eca36,
    author = "Clemens, W. and Allison, C.",
    title = "Late Cretaceous terrestrial vertebrate fauna, North Slope, Alaska",
    year = "1985",
    journal = "Geol. Soc. Am., Abstr. Programs; (United States)",
    abstract = "Closely related terrestrial vertebrates in Cretaceous mid-latitude (30/sup 0/ to 50/sup 0/) faunas of North America and Asia as well as scattered occurrences of footprints and skin impressions suggested that in the Late Mesozoic the Alaskan North Slope supported a diverse fauna. In 1961 abundant skeletal elements of Cretaceous, Alaskan dinosaurs (hadrosaurids) were discovered by the late R.L. Liscomb. This material is being described by K.L. Davies. Additional fossils collected by E.M. Brouwers and her associates include skeletal elements of hadrosaurid and carnosaurian (.tyrannosaurid) dinosaurs and other vertebrates. The fossil locality on the North Slope is not at about 70/sup 0/N. In the Late Cretaceous the members of this fauna were subject to the daylight regime and environment at a paleolatitude closer to 80/sup 0/N. Current hypotheses attributing extinctions of dinosaurs and some other terrestrial vertebrates to impact of an extraterrestrial object cite periods of darkness, decreased temperature (possibly followed by extreme warming) and acid rain as the direct causes of their demise. Unless members of this North Slope fauna undertook long-distance migrations, their high latitude occurrence indicates groups of dinosaurs and other terrestrial vertebrates regularly tolerated months of darkness.",
    url = "https://www.semanticscholar.org/paper/7d8bedefc50ce4561424495457a173f1e18eca36",
    is_oa = "true",
    openalex = "W53920284",
    semanticscholar_citation_count = "13",
    semanticscholar_id = "7d8bedefc50ce4561424495457a173f1e18eca36"
}

Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian—early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed of coniferous and broad leaf trees. The high paleolatitude (about 70° to 85° North) implies extreme seasonal variation in solar insolation, temperature, and herbivore food supply. Great distances of migration to contemporaneous evergreen floras and the presence of both juvenile and adult hadrosaurs suggest that they remained at high latitudes year-round. This challenges the hypothesis that short-term periods of darkness and temperature decrease resulting from a bolide impact caused dinosaurian extinction.

@article{brouwers1987dinosaurs,
    author = "Brouwers, Elisabeth M. and Clemens, William A. and Spicer, Robert A. and Ager, Thomas A. and Carter, L. David and Sliter, William V.",
    title = "Dinosaurs on the North Slope, Alaska: High Latitude, Latest Cretaceous Environments",
    year = "1987",
    journal = "Science",
    abstract = "Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian—early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed of coniferous and broad leaf trees. The high paleolatitude (about 70° to 85° North) implies extreme seasonal variation in solar insolation, temperature, and herbivore food supply. Great distances of migration to contemporaneous evergreen floras and the presence of both juvenile and adult hadrosaurs suggest that they remained at high latitudes year-round. This challenges the hypothesis that short-term periods of darkness and temperature decrease resulting from a bolide impact caused dinosaurian extinction.",
    url = "https://doi.org/10.1126/science.237.4822.1608",
    doi = "10.1126/science.237.4822.1608",
    number = "4822",
    pages = "1608-1610",
    volume = "237"
}

Hadrosaur Bones have been found on the Colville River north of Umiat on the North Slope of Alaska. This find represents the first report of dinosaur bones in Alaska and their northernmost reported occurrence. The remains are not determinable below family level but are important, nonetheless, for interpretations of the paleoclimatology and paleobiogeography of the Late Cretaceous.

@article{davies1987duckbill,
    author = "Davies, Kyle L.",
    title = "Duck-bill dinosaurs (Hadrosauridae, Ornithischia) from the North Slope of Alaska",
    year = "1987",
    journal = "Journal of Paleontology",
    abstract = "Hadrosaur Bones have been found on the Colville River north of Umiat on the North Slope of Alaska. This find represents the first report of dinosaur bones in Alaska and their northernmost reported occurrence. The remains are not determinable below family level but are important, nonetheless, for interpretations of the paleoclimatology and paleobiogeography of the Late Cretaceous.",
    url = "https://doi.org/10.1017/s0022336000028341",
    doi = "10.1017/s0022336000028341",
    number = "1",
    pages = "198-200",
    volume = "61"
}

@article{davies1987duckbill1,
    author = "Davies, K. L",
    title = "Duckbill dinosaurs from the North Slope of Alaska",
    year = "1987",
    journal = "Journal of Paleontology, v. 61, p. 198-200",
    note = "talkorigins\_source = {true}; raw\_reference = {Davies, K. L., 1987, Duckbill dinosaurs from the North Slope of Alaska: Journal of Paleontology, v. 61, p. 198-200.}"
}

Hadrosaur Bones have been found on the Colville River north of Umiat on the North Slope of Alaska. This find represents the first report of dinosaur bones in Alaska and their northernmost reported occurrence. The remains are not determinable below family level but are important, nonetheless, for interpretations of the paleoclimatology and paleobiogeography of the Late Cretaceous.

@article{doi101017s0022336000028341,
    author = "Davies, Kyle L.",
    title = "Duck-bill dinosaurs (Hadrosauridae, Ornithischia) from the North Slope of Alaska",
    year = "1987",
    journal = "Journal of Paleontology",
    abstract = "Hadrosaur Bones have been found on the Colville River north of Umiat on the North Slope of Alaska. This find represents the first report of dinosaur bones in Alaska and their northernmost reported occurrence. The remains are not determinable below family level but are important, nonetheless, for interpretations of the paleoclimatology and paleobiogeography of the Late Cretaceous.",
    url = "https://www.semanticscholar.org/paper/f55b1039b83338550eb77ee878676518aae8f885",
    doi = "10.1017/S0022336000028341",
    is_oa = "true",
    number = "1",
    pages = "198-200",
    semanticscholar_citation_count = "40",
    semanticscholar_id = "f55b1039b83338550eb77ee878676518aae8f885",
    volume = "61"
}

@article{parrish1987late,
    author = "Parrish, J. Michael and Parrish, Judith Totman and Hutchison, J. Howard and Spicer, Robert A.",
    title = "Late Cretaceous Vertebrate Fossils from the North Slope of Alaska and Implications for Dinosaur Ecology",
    year = "1987",
    journal = "PALAIOS",
    url = "https://doi.org/10.2307/3514763",
    doi = "10.2307/3514763",
    number = "4",
    openalex = "W2317865496",
    pages = "377",
    volume = "2",
    references = "davies1987duckbill, doi1010160012825283900016, doi101038274661a0, doi101038324148a0, doi101086284369, doi101086284406, doi101130spe40p1, doi101146annurevea05050177001535, doi1023071444927, doi1023072937268, doi102475ajs2628975, doi104095105049, doi105479si00963801361666197, openalexw2204429280"
}

The discovery well for the Prudhoe Bay field, the largest oil accumulatn yet found in the United States, was drilled on the Arctic coast of Alaska by ARCO and Exxon in 1968. A decade of exploratory geology and increasingly detailed geophysical surveys, mostly by Sinclair and British Petroleum in the early years, but then by a number of companies, preceded the discovery. Systematic U.S. Geological Survey (USGS) reconnaissance of the Brooks Range—the great mountain system of northern Alaska—had begun in the 1940s and was accelerated after the discovery, as was industry work. In the last decade, scientists from the Alaska Division of Geology and Geophysics and from various universities have become increasingly involved. This modestly priced two‐volume work presents hitherto unavailable summaries of much of this modern work.

@article{doi10102988eo01126,
    author = "Hamilton, Warren",
    title = "Alaskan North Slope Geology",
    year = "1988",
    journal = "Eos",
    abstract = "The discovery well for the Prudhoe Bay field, the largest oil accumulatn yet found in the United States, was drilled on the Arctic coast of Alaska by ARCO and Exxon in 1968. A decade of exploratory geology and increasingly detailed geophysical surveys, mostly by Sinclair and British Petroleum in the early years, but then by a number of companies, preceded the discovery. Systematic U.S. Geological Survey (USGS) reconnaissance of the Brooks Range—the great mountain system of northern Alaska—had begun in the 1940s and was accelerated after the discovery, as was industry work. In the last decade, scientists from the Alaska Division of Geology and Geophysics and from various universities have become increasingly involved. This modestly priced two‐volume work presents hitherto unavailable summaries of much of this modern work.",
    url = "https://doi.org/10.1029/88eo01126",
    doi = "10.1029/88eo01126",
    openalex = "W2168999206"
}

The principal aim of the second period of exploration became the acquisition of knowledge - the discovery of oil or gas was a hoped-for, but yet secondary, objective. This report provides a historical overview of this more recent (1975-1982) exploration. It was prepared originally to serve as a unifying prologue for a series of contract reports by Husky Oil NPR Operations, Inc., concerning various phases of the project. The program of Government exploration and investigation of the oil resources of the Alaskan North Slope spans a period of 38 years (1944 to 1982) and has witnessed the use of many types of equipment, methods of investigation, and logistical support. All of this reflects the progress in technology and an increased respect for the environment. The severe climate of the Arctic has been an overriding influence affecting plans, budgets, and operations. Few other areas of the world require such attention to climatic constraints. The second (1975-1982) exploration program was built on the earlier experience of the U.S. Navy and also on lessons learned at Prudhoe Bay. It evolved into a sophisticated operation and its successful execution is a tribute to all of the personnel involved.

@article{openalexw251474935,
    author = "Schindler, J.",
    title = "History of exploration in the National Petroleum Reserve in Alaska, with emphasis on the period from 1975 to 1982",
    year = "1989",
    journal = "OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information)",
    abstract = "The principal aim of the second period of exploration became the acquisition of knowledge - the discovery of oil or gas was a hoped-for, but yet secondary, objective. This report provides a historical overview of this more recent (1975-1982) exploration. It was prepared originally to serve as a unifying prologue for a series of contract reports by Husky Oil NPR Operations, Inc., concerning various phases of the project. The program of Government exploration and investigation of the oil resources of the Alaskan North Slope spans a period of 38 years (1944 to 1982) and has witnessed the use of many types of equipment, methods of investigation, and logistical support. All of this reflects the progress in technology and an increased respect for the environment. The severe climate of the Arctic has been an overriding influence affecting plans, budgets, and operations. Few other areas of the world require such attention to climatic constraints. The second (1975-1982) exploration program was built on the earlier experience of the U.S. Navy and also on lessons learned at Prudhoe Bay. It evolved into a sophisticated operation and its successful execution is a tribute to all of the personnel involved.",
    openalex = "W251474935"
}

@incollection{doi101007978146848276815,
    author = "McMillen, Kenneth J.",
    title = "Seismic Stratigraphy of Lower Cretaceous Foreland Basin Submarine Fans in the North Slope, Alaska",
    year = "1991",
    booktitle = "Frontiers in sedimentary geology",
    url = "https://doi.org/10.1007/978-1-4684-8276-8\_15",
    doi = "10.1007/978-1-4684-8276-8\_15",
    openalex = "W36038956",
    references = "mickey1985jurassicneocomian"
}

@article{doi103133ofr88450y,
    author = "Bird, Kenneth J.",
    title = "Geology, play descriptions, and petroleum resources of the Alaskan North Slope (petroleum provinces 58-60)",
    year = "1991",
    journal = "Antarctica A Keystone in a Changing World",
    url = "https://doi.org/10.3133/ofr88450y",
    doi = "10.3133/ofr88450y",
    openalex = "W1526664325",
    references = "openalexw251474935"
}

Earlier studies of terrestrial heat flow in the North Slope Basin, Alaska, found that heat flow varies systematically in a trend perpendicular to the strike of basin strata and the neighboring Brooks Range. Heat flow (∼±20%) increases from a low of 27 mW/m 2 in the foothills of the Brooks Range in the south to a high of 90 mW/m 2 on the coastal plain to the north. The thermal pattern can be explained by a regional‐scale (∼330 km) groundwater flow system which transports heat by advection from regions of high elevation in the Brooks Range and its foothills to lower elevations on the Arctic coastal plain. Permeability data from 2031 core measurements made parallel to bedding and 15 well tests were compiled for 10 geologic units. Arithmetic‐mean permeabilities derived from measurements on core samples range from 2.2 × 10 −13 m 2 for sandstones of the Endicott Group to 1.1 × 10 −16 m 2 for limestones of the Lisburne Group. The arithmetic‐mean permeability derived from all 2031 core measurements made parallel to bedding is 6.1 × 10 −14 m 2. A numerical model of coupled heat and fluid flow in the North Slope Basin was constructed and a series of model simulations were conducted. A model simulation incorporating permeability data obtained from core measurements resulted in a good match to observed heat flow data, apparently suggesting that permeability in the North Slope Basin does not increase significantly from the core scale (∼10 −2 ‐ 10 −1 m) to the basin scale (∼10 5 –10 6 m). This inference, however, is complicated by the possible effects of factors such as sample bias in measurements and choice of an appropriate averaging algorithm. A further series of model simulations were done in which the specified model permeability was homogeneous and anisotropic. Comparisons of heat flow predicted by these simulations with heat flow determined in field studies suggested that the effective basin‐scale permeability parallel to bedding (k x) is in the range of 2.5 × 10 −14 ≤ K x ≤ 2.5 × 10 −13 m 2 and permeability perpendicular to bedding (k z) is in the range of 1.0 ×10 −16 ≤ k z ≤ 5.0 × 10 −16 m 2. These constraints depend upon the explicit assumption that groundwater flow is the only mechanism responsible for heat flow variations across the North Slope Basin.

@article{doi10102993jb01427,
    author = "Deming, David",
    title = "Regional permeability estimates from investigations of coupled heat and groundwater flow, north slope of alaska",
    year = "1993",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Earlier studies of terrestrial heat flow in the North Slope Basin, Alaska, found that heat flow varies systematically in a trend perpendicular to the strike of basin strata and the neighboring Brooks Range. Heat flow (∼±20\%) increases from a low of 27 mW/m 2 in the foothills of the Brooks Range in the south to a high of 90 mW/m 2 on the coastal plain to the north. The thermal pattern can be explained by a regional‐scale (∼330 km) groundwater flow system which transports heat by advection from regions of high elevation in the Brooks Range and its foothills to lower elevations on the Arctic coastal plain. Permeability data from 2031 core measurements made parallel to bedding and 15 well tests were compiled for 10 geologic units. Arithmetic‐mean permeabilities derived from measurements on core samples range from 2.2 × 10 −13 m 2 for sandstones of the Endicott Group to 1.1 × 10 −16 m 2 for limestones of the Lisburne Group. The arithmetic‐mean permeability derived from all 2031 core measurements made parallel to bedding is 6.1 × 10 −14 m 2. A numerical model of coupled heat and fluid flow in the North Slope Basin was constructed and a series of model simulations were conducted. A model simulation incorporating permeability data obtained from core measurements resulted in a good match to observed heat flow data, apparently suggesting that permeability in the North Slope Basin does not increase significantly from the core scale (∼10 −2 ‐ 10 −1 m) to the basin scale (∼10 5 –10 6 m). This inference, however, is complicated by the possible effects of factors such as sample bias in measurements and choice of an appropriate averaging algorithm. A further series of model simulations were done in which the specified model permeability was homogeneous and anisotropic. Comparisons of heat flow predicted by these simulations with heat flow determined in field studies suggested that the effective basin‐scale permeability parallel to bedding (k x) is in the range of 2.5 × 10 −14 ≤ K x ≤ 2.5 × 10 −13 m 2 and permeability perpendicular to bedding (k z) is in the range of 1.0 ×10 −16 ≤ k z ≤ 5.0 × 10 −16 m 2. These constraints depend upon the explicit assumption that groundwater flow is the only mechanism responsible for heat flow variations across the North Slope Basin.",
    url = "https://doi.org/10.1029/93jb01427",
    doi = "10.1029/93jb01427",
    openalex = "W2031957914",
    references = "birdNonenorth, doi1010291998wr900047, doi10102991eo00190, doi101029jb088ib01p00593, doi101029jb090ib08p06817, doi101130001676061973843803taofch20co2, doi101146annurevea18050190001443, doi1013065ceadd6116bb11d78645000102c1865d, doi101306m60585, doi105860choice352126, openalexw2112906818"
}

Geological and geochemical data have been interpreted to identify areas of mineral resource potential in the Killik River quadrangle, north-central Alaska.The quadrangle consists mainly of clastic and carbonate sedimentary rocks, with minor extrusive and intrusive mafic igneous rocks.The types of mineral deposits expected to occur in the quadrangle are stratiform and (or) stratabound deposits.Therefore, geologic tracts favorable for hosting mineral deposits are defined by geochemical data within the boundaries of host rock lithologies.A broad tract in the central part of the quadrangle is characterized by chert and shale of Mississippian to Jurassic age.Three small areas within this tract have a moderate potential for resources of lead, silver, and zinc (± barium) in sedimentary exhalative massive sulfide deposits in rocks of primarily Mississippian and Pennsylvanian age; the remaining area has a low potential.The southern third of the quadrangle is underlrin by Upper Devonian and Lower Mississippian(?) clastic rocks of the Hunt Fork Shale, Noatak Sandstone, and Kanayut Conglomerate.Geochemical data indicate that approximately 40 percent of this area has a high potential for stratabound veins and vein-breccias containing resources for lead, silver, and zinc (± gold and copper).The remaining 60 percent of the area, which consists of clastic rocks, has a moderate potential for such deposits.Chert, shale, and carbonate rocks permissive for hosting sedimentary barite, manganese, or phosphate deposits comprise much of the central and western parts of the quadrangle.Six small areas have moderate potential for barite resources, seven have moderate potential for manganese resources, and two areas have moderate potential for phosphate resources.Mafic pillow basalts and associated chert, exposed in two small areas (<10 km2) in the central part of the quadrangle, are permissive for copper and zinc resources in Cypristype massive sulfide deposits.However, the relatively small volume of the mafic rocks and available geochemical data indicate that these areas have a low resource potential.Nonmarine sedimentary rocks of the Cretaceous Nanushuk Group comprise the northern part of the quadrangle.Although these rocks are permissive host rocks for roll-front type uranium deposits (± copper and vanadium), placer deposits (chromium ± platinum group elements and gold), and coal, geochemical data suggest there is a low resource potential for all commodities.Although the mountainous southern third of the quadrangle has no potential for petroleum resources, tl ^re is potential in the northern two-thirds.Potential source beds are present in black shale and limestone with high organic content, and the presence of hydrocarbon in porous dolomite suggests that generation and migration of hydrocarbons did occur.However, with the available data it is difficult to evaluate the relationship between the timing of hydrocarbon generation, migration, and trapping that must be considered to fully evaluate the level of potential.Therefore, the hydrocarbon potential is uncertain.to the President and Congress.This report presents geologic, geochemical, and mineralogical data that delineate areas in the Killik River quadrangle with potential for mineral resources.

@misc{doi103133mf2225a,
    author = "Kelley, Karen D. and Mull, Charles G.",
    title = "Maps showing areas of potential for mineral resources in the Killik River 1° x 3° quadrangle, Alaska",
    year = "1995",
    abstract = "Geological and geochemical data have been interpreted to identify areas of mineral resource potential in the Killik River quadrangle, north-central Alaska.The quadrangle consists mainly of clastic and carbonate sedimentary rocks, with minor extrusive and intrusive mafic igneous rocks.The types of mineral deposits expected to occur in the quadrangle are stratiform and (or) stratabound deposits.Therefore, geologic tracts favorable for hosting mineral deposits are defined by geochemical data within the boundaries of host rock lithologies.A broad tract in the central part of the quadrangle is characterized by chert and shale of Mississippian to Jurassic age.Three small areas within this tract have a moderate potential for resources of lead, silver, and zinc (± barium) in sedimentary exhalative massive sulfide deposits in rocks of primarily Mississippian and Pennsylvanian age; the remaining area has a low potential.The southern third of the quadrangle is underlrin by Upper Devonian and Lower Mississippian(?) clastic rocks of the Hunt Fork Shale, Noatak Sandstone, and Kanayut Conglomerate.Geochemical data indicate that approximately 40 percent of this area has a high potential for stratabound veins and vein-breccias containing resources for lead, silver, and zinc (± gold and copper).The remaining 60 percent of the area, which consists of clastic rocks, has a moderate potential for such deposits.Chert, shale, and carbonate rocks permissive for hosting sedimentary barite, manganese, or phosphate deposits comprise much of the central and western parts of the quadrangle.Six small areas have moderate potential for barite resources, seven have moderate potential for manganese resources, and two areas have moderate potential for phosphate resources.Mafic pillow basalts and associated chert, exposed in two small areas (<10 km2) in the central part of the quadrangle, are permissive for copper and zinc resources in Cypristype massive sulfide deposits.However, the relatively small volume of the mafic rocks and available geochemical data indicate that these areas have a low resource potential.Nonmarine sedimentary rocks of the Cretaceous Nanushuk Group comprise the northern part of the quadrangle.Although these rocks are permissive host rocks for roll-front type uranium deposits (± copper and vanadium), placer deposits (chromium ± platinum group elements and gold), and coal, geochemical data suggest there is a low resource potential for all commodities.Although the mountainous southern third of the quadrangle has no potential for petroleum resources, tl ^re is potential in the northern two-thirds.Potential source beds are present in black shale and limestone with high organic content, and the presence of hydrocarbon in porous dolomite suggests that generation and migration of hydrocarbons did occur.However, with the available data it is difficult to evaluate the relationship between the timing of hydrocarbon generation, migration, and trapping that must be considered to fully evaluate the level of potential.Therefore, the hydrocarbon potential is uncertain.to the President and Congress.This report presents geologic, geochemical, and mineralogical data that delineate areas in the Killik River quadrangle with potential for mineral resources.",
    url = "https://doi.org/10.3133/mf2225a",
    doi = "10.3133/mf2225a",
    openalex = "W133056753",
    references = "doi1010079783662086810, doi1010160375674275900242, doi101016b9780444418241500116, doi10130603b59b0c16d111d78645000102c1865d, doi102113gsecongeo8071896, doi105382mono08, doi105962bhltitle61914, openalexw2140021650, openalexw2474911968, openalexw251474935, tourtelot1971the"
}

ABSTRACT Regional crustal shortening in northern Yukon and northeastern Alaska occurred episodically from the latest Cretaceous to the late Miocene, with a major culmination occurring in the Paleocene to middle Eocene, and a secondary culmination in the late Miocene. Structural trends are predominantly north to northeastward in northern Yukon and adjacent east-central Alaska, and generally east-west along the Brooks Range. The early Tertiary trend is strongly arcuate in the Beaufort fold belt and adjacent onshore areas. The continuity of structures southward from the Beaufort Sea region through northern Yukon and east-central Alaska supports the interpretation that the structures north of 65°N form a single orogenic entity. The Beaufort Sea region is 1000 km from the nearest plate margin. Northward shortening across Arctic Alaska and the northern Canadian cordillera reflects the convergent component of Kula (later, Pacific)–North America interactions throughout the Tertiary. North-to northeast-trending structures of latest Cretaceous to early Tertiary age in northern Yukon and east-central Alaska accommodate shortening of 180–240 km, and reflect Eurasia–North America convergence. The strongly arcuate offshore Beaufort fold belt and similar structures in adjacent northernmost Yukon and northeast Alaska were formed by the complex interplay of three factors: shortening of northern Yukon between Arctic Alaska and the craton to produce a north-trending orogenic welt; northward displacements propagated from the Kula plate margin; and local boundary conditions imposed by lithology and crustal structure, which aided lateral escape of the deforming supracrustal succession northward into the Beaufort Sea. In central Alaska, any kinematic linkage between the Kaltag fault in the west and the Tintina fault of the northern cordillera is more complex than was previously assumed. A new regional tectonic reconstruction of northern Yukon-Alaska quantifies the tectonic shortening in central Alaska south of the Kaltag and Tintina faults in an area where tectonic shortening is difficult to quantify due to complex geology. Complex deformation accommodated by folding, thrust and strike-slip faulting, and/or tectonic rotations accounts for an estimated 460 km of crustal shortening, approximately equivalent in magnitude to the total Tintina fault displacement of at least 450 km. The foreland of the Brooks Range, the Beaufort fold belt, and the northern cordillera contain proven petroleum basins. This regional synthesis validates a model of orogenic shortening for the Beaufort fold belt and provides a unifying tectonic setting for oil and gas plays throughout the region. The latest Cretaceous–Tertiary structural evolution of the Brooks Range, Beaufort, and northern Yukon fold belts is a case study of the temporally and kinematically complex far-field deformation arising from the convergence of four major tectonic plates.

@article{doi1013061d9bca75172d11d78645000102c1865d,
    author = "Lane, L S",
    title = "Latest Cretaceous—Tertiary Tectonic Evolution of Northern Yukon and Adjacent Arctic Alaska",
    year = "1998",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Regional crustal shortening in northern Yukon and northeastern Alaska occurred episodically from the latest Cretaceous to the late Miocene, with a major culmination occurring in the Paleocene to middle Eocene, and a secondary culmination in the late Miocene. Structural trends are predominantly north to northeastward in northern Yukon and adjacent east-central Alaska, and generally east-west along the Brooks Range. The early Tertiary trend is strongly arcuate in the Beaufort fold belt and adjacent onshore areas. The continuity of structures southward from the Beaufort Sea region through northern Yukon and east-central Alaska supports the interpretation that the structures north of 65°N form a single orogenic entity. The Beaufort Sea region is 1000 km from the nearest plate margin. Northward shortening across Arctic Alaska and the northern Canadian cordillera reflects the convergent component of Kula (later, Pacific)–North America interactions throughout the Tertiary. North-to northeast-trending structures of latest Cretaceous to early Tertiary age in northern Yukon and east-central Alaska accommodate shortening of 180–240 km, and reflect Eurasia–North America convergence. The strongly arcuate offshore Beaufort fold belt and similar structures in adjacent northernmost Yukon and northeast Alaska were formed by the complex interplay of three factors: shortening of northern Yukon between Arctic Alaska and the craton to produce a north-trending orogenic welt; northward displacements propagated from the Kula plate margin; and local boundary conditions imposed by lithology and crustal structure, which aided lateral escape of the deforming supracrustal succession northward into the Beaufort Sea. In central Alaska, any kinematic linkage between the Kaltag fault in the west and the Tintina fault of the northern cordillera is more complex than was previously assumed. A new regional tectonic reconstruction of northern Yukon-Alaska quantifies the tectonic shortening in central Alaska south of the Kaltag and Tintina faults in an area where tectonic shortening is difficult to quantify due to complex geology. Complex deformation accommodated by folding, thrust and strike-slip faulting, and/or tectonic rotations accounts for an estimated 460 km of crustal shortening, approximately equivalent in magnitude to the total Tintina fault displacement of at least 450 km. The foreland of the Brooks Range, the Beaufort fold belt, and the northern cordillera contain proven petroleum basins. This regional synthesis validates a model of orogenic shortening for the Beaufort fold belt and provides a unifying tectonic setting for oil and gas plays throughout the region. The latest Cretaceous–Tertiary structural evolution of the Brooks Range, Beaufort, and northern Yukon fold belts is a case study of the temporally and kinematically complex far-field deformation arising from the convergence of four major tectonic plates.",
    url = "https://doi.org/10.1306/1d9bca75-172d-11d7-8645000102c1865d",
    doi = "10.1306/1d9bca75-172d-11d7-8645000102c1865d",
    openalex = "W1997624702",
    references = "doi101139e72101"
}

@article{doi101016s014663800000187x,
    author = "Masterson, W. Dallam and Dzou, Leon and Holba, Á. and Fincannon, Ann L and Ellis, Leroy",
    title = "Evidence for biodegradation and evaporative fractionation in West Sak, Kuparuk and Prudhoe Bay field areas, North Slope, Alaska",
    year = "2001",
    journal = "Organic Geochemistry",
    url = "https://doi.org/10.1016/s0146-6380(00)00187-x",
    doi = "10.1016/s0146-6380(00)00187-x",
    openalex = "W2078395080"
}

Lower Paleozoic platform carbonate strata in northern Alaska (parts of the Arctic Alaska, York, and Seward terranes; herein called the North Alaska carbonate platform) and central Alaska (Farewell terrane) share distinctive lithologic and faunal features, and may have formed on a single continental fragment situated between Siberia and Laurentia. Sedimentary successions in northern and central Alaska overlie Late Proterozoic metamorphosed basement; contain Late Proterozoic ooid-rich dolostones, Middle Cambrian outer shelf deposits, and Ordovician, Silurian, and Devonian shallow-water platform facies, and include fossils of both Siberian and Laurentian biotic provinces. The presence in the Alaskan terranes of Siberian forms not seen in wellstudied cratonal margin sequences of western Laurentia implies that the Alaskan rocks were not attached to Laurentia during the early Paleozoic. The Siberian cratonal succession includes Archean basement, Ordovician shallow-water siliciclastic rocks, and Upper Silurian-Devonian evaporites, none of which have counterparts in the Alaskan successions, and contains only a few of the Laurentian conodonts that occur in Alaska. Thus we conclude that the lower Paleozoic platform successions of northern and central Alaska were not part of the Siberian craton during their deposition, but may have formed on a crustal fragment rifted away from Siberia during the Late Proterozoic. The Alaskan strata have more similarities to coeval rocks in some peri-Siberian terranes of northeastern Russia (Kotelny, Chukotka, and Omulevka). Lithologic ties between northern Alaska, the Farewell terrane, and the peri-Siberian terranes diminish after the Middle Devonian, but Siberian affinities in northern and central Alaskan biotas persist into the late Paleozoic.

@incollection{doi1011300813723604291,
    author = "Dumoulin, Julie A. and Harris, Anita G. and Gagiev, M.H. and Bradley, Dwight C. and Repetski, John E.",
    title = "Lithostratigraphic, conodont, and other faunal links between lower Paleozoic strata in northern and central Alaska and northeastern Russia",
    year = "2002",
    booktitle = "Geological Society of America eBooks",
    abstract = "Lower Paleozoic platform carbonate strata in northern Alaska (parts of the Arctic Alaska, York, and Seward terranes; herein called the North Alaska carbonate platform) and central Alaska (Farewell terrane) share distinctive lithologic and faunal features, and may have formed on a single continental fragment situated between Siberia and Laurentia. Sedimentary successions in northern and central Alaska overlie Late Proterozoic metamorphosed basement; contain Late Proterozoic ooid-rich dolostones, Middle Cambrian outer shelf deposits, and Ordovician, Silurian, and Devonian shallow-water platform facies, and include fossils of both Siberian and Laurentian biotic provinces. The presence in the Alaskan terranes of Siberian forms not seen in wellstudied cratonal margin sequences of western Laurentia implies that the Alaskan rocks were not attached to Laurentia during the early Paleozoic. The Siberian cratonal succession includes Archean basement, Ordovician shallow-water siliciclastic rocks, and Upper Silurian-Devonian evaporites, none of which have counterparts in the Alaskan successions, and contains only a few of the Laurentian conodonts that occur in Alaska. Thus we conclude that the lower Paleozoic platform successions of northern and central Alaska were not part of the Siberian craton during their deposition, but may have formed on a crustal fragment rifted away from Siberia during the Late Proterozoic. The Alaskan strata have more similarities to coeval rocks in some peri-Siberian terranes of northeastern Russia (Kotelny, Chukotka, and Omulevka). Lithologic ties between northern Alaska, the Farewell terrane, and the peri-Siberian terranes diminish after the Middle Devonian, but Siberian affinities in northern and central Alaskan biotas persist into the late Paleozoic.",
    url = "https://doi.org/10.1130/0-8137-2360-4.291",
    doi = "10.1130/0-8137-2360-4.291",
    openalex = "W2290759071",
    references = "doi103133cir967"
}

Synopsis The dinosaurs of the Hateg Basin of Transylvania (late Maastrichtian; western Romania) include Theropoda, Sauropoda, Ornithopoda and Ankylosauria. Of these, one of the most enigmatic taxa is the ornithopod that Franz Baron Nopcsa originally described as Mochlodon suessi and M. robustus in 1902. These two species have come to be regarded as a single species of Rhabdodon, R. robustus, which is distinct from R. priscus from the Late Cretaceous of southern France and northern Spain. This study provides a detailed anatomical revision of the Rhabdodon material that was described originally by Nopcsa during the early decades of the 20th century. It also adds information on material discovered in the Hateg area of Romania since the 1930s. A phylogenetic analysis of basal euornithopods indicates that the non‐hadrosaurid material from Hateg comprises two distinct, but congeneric, species. These two species can be distinguished unambiguously from R. priscus. A new genus Zalmoxes is established for the Romanian ornithopod, comprising Z. robustus comb. nov. (the type‐species of the genus) and Z. shqiperorum sp. nov. Phylogenetic analysis indicates that the two species of Zalmoxes and R. priscus are united in the monophyletic clade Rhabdodontidae (nov.). Rhabdodontidae constitutes the sibling clade to Iguanodontia. R. septimanicus, M. suessi, and the Villeveyrac Rhabdodon also appear to be members of Rhabdodontidae. The evolutionary implications of this phylogenetic analysis include the recognition of a ghost lineage, extending from the most recent common ancestor of Rhabdodontidae and Iguanodontia, which extends for 73 million years. This extraordinarily long ghost lineage duration may reflect considerable gaps in the history of this group or the geographical isolation of Rhabdodontidae in Europe during much of the Cretaceous period. The area of origin of the Rhabdodontidae + Iguanodontia clade may be North America, while the common ancestor of Rhabdodontidae dispersed to Europe, at that time a marine‐dominated region with tectonically‐active terrestrial habitats. Adult individuals of Z. robustus are smaller than either of its two closest relatives, Z. shqiperorum and R. priscus, within the Rhabdodontidae, or with many species of Iguanodontia and, therefore, is considered a possible paedomorphic dwarf.

@article{doi101017s1477201903001032,
    author = "Weishampel, David B. and Jianu, Coralia‐Maria and Csiki‐Sava, Zoltán and Norman, David",
    title = "Osteology and phylogeny of Zalmoxes (n. g.), an unusual Euornithopod dinosaur from the latest Cretaceous of Romania",
    year = "2003",
    journal = "Journal of Systematic Palaeontology",
    abstract = "Synopsis The dinosaurs of the Hateg Basin of Transylvania (late Maastrichtian; western Romania) include Theropoda, Sauropoda, Ornithopoda and Ankylosauria. Of these, one of the most enigmatic taxa is the ornithopod that Franz Baron Nopcsa originally described as Mochlodon suessi and M. robustus in 1902. These two species have come to be regarded as a single species of Rhabdodon, R. robustus, which is distinct from R. priscus from the Late Cretaceous of southern France and northern Spain. This study provides a detailed anatomical revision of the Rhabdodon material that was described originally by Nopcsa during the early decades of the 20th century. It also adds information on material discovered in the Hateg area of Romania since the 1930s. A phylogenetic analysis of basal euornithopods indicates that the non‐hadrosaurid material from Hateg comprises two distinct, but congeneric, species. These two species can be distinguished unambiguously from R. priscus. A new genus Zalmoxes is established for the Romanian ornithopod, comprising Z. robustus comb. nov. (the type‐species of the genus) and Z. shqiperorum sp. nov. Phylogenetic analysis indicates that the two species of Zalmoxes and R. priscus are united in the monophyletic clade Rhabdodontidae (nov.). Rhabdodontidae constitutes the sibling clade to Iguanodontia. R. septimanicus, M. suessi, and the Villeveyrac Rhabdodon also appear to be members of Rhabdodontidae. The evolutionary implications of this phylogenetic analysis include the recognition of a ghost lineage, extending from the most recent common ancestor of Rhabdodontidae and Iguanodontia, which extends for 73 million years. This extraordinarily long ghost lineage duration may reflect considerable gaps in the history of this group or the geographical isolation of Rhabdodontidae in Europe during much of the Cretaceous period. The area of origin of the Rhabdodontidae + Iguanodontia clade may be North America, while the common ancestor of Rhabdodontidae dispersed to Europe, at that time a marine‐dominated region with tectonically‐active terrestrial habitats. Adult individuals of Z. robustus are smaller than either of its two closest relatives, Z. shqiperorum and R. priscus, within the Rhabdodontidae, or with many species of Iguanodontia and, therefore, is considered a possible paedomorphic dwarf.",
    url = "https://doi.org/10.1017/s1477201903001032",
    doi = "10.1017/s1477201903001032",
    openalex = "W2167550757",
    references = "doi10100797836426953391, doi10103835059070, doi10108002724634199010011815, doi101086284406, doi101098rspl18870117, doi101111j109636421998tb02533x, doi101126science27352791204, doi102307jctvxkn7tk, doi102475ajss321125417, doi105479si00963801361666197, openalexw51761775, openalexw575814759"
}

This book identifies accumulated environmental, social and economic effects of oil and gas leasing, exploration, and production on Alaska's North Slope. Economic benefits to the region have been accompanied by effects of the roads, infrastructure and activies of oil and gas production on the terrain, plants, animals and peoples of the North Slope. While attempts by the oil industry and regulatory agencies have reduced many of the environmental effects, they have not been eliminated. The book makes recommendations for further environmental research related to environmental effects.

@book{doi101722610639,
    author = "Council, National Research",
    title = "Cumulative Environmental Effects of Oil and Gas Activities on Alaska's North Slope",
    year = "2003",
    booktitle = "National Academies Press eBooks",
    abstract = "This book identifies accumulated environmental, social and economic effects of oil and gas leasing, exploration, and production on Alaska's North Slope. Economic benefits to the region have been accompanied by effects of the roads, infrastructure and activies of oil and gas production on the terrain, plants, animals and peoples of the North Slope. While attempts by the oil industry and regulatory agencies have reduced many of the environmental effects, they have not been eliminated. The book makes recommendations for further environmental research related to environmental effects.",
    url = "https://doi.org/10.17226/10639",
    doi = "10.17226/10639",
    openalex = "W645166368"
}

Abstract Previous studies of the areal variation in heat flow in the National Petroleum Reserve Alaska (NPRA) support the existence of an active topographically driven regional fluid flow regime in this central part of the North Slope foreland basin. Drilling records and wireline logs for over 30 wells drilled in the NPRA provide additional field information, which can be used to further constrain interpretation of the pattern of regional flow of basinal waters within the NPRA. Hydraulic heads estimated from drilling mud weights show that ground water flow occurs generally from south to north, but with divergence to the north‐east and north‐west away from the central part of the NPRA towards coastal areas of elevated shallow heat flow. Salinities calculated from SP logs range from less than 1 g L −1, to marine values of 35 g L −1, to hypersaline values of over 150 g L −1. The entire upper sedimentary section to a depth of 2 km or more in the eastern part of the NPRA has been preferentially flushed with meteoric water through an area corresponding to the sandiest portion of the Nanushuk group. Deeper areas of low salinity occur within the Sadlerochit and Lisburne sections. The pattern of regional flow in the east is complicated, however, by the presence of a large mass of hypersaline water at depth. It is not known whether these brines are being displaced laterally and upward towards the discharge end of the basin or whether fresher waters are simply riding up over the top. Deep, hypersaline waters also occur in fault slices in the Brooks Range and have survived meteoric flushing. The brines were probably formed at the time of deposition of the Lisburne carbonates. The fluid flow regime to the west is different. Low‐salinity waters may be flowing northward underneath this section through the Ellesmerian section and discharging upward nearer the coast. However, sparse well log control severely limits what can be deduced about the details of flow paths in the central and western parts of the NPRA.

@article{doi101111j14688115200400079x,
    author = "Hanor, J. S. and Nunn, Jeffrey A. and Lee, Y.",
    title = "Salinity structure of the central North Slope foreland basin, Alaska, USA: implications for pathways of past and present topographically driven regional fluid flow",
    year = "2004",
    journal = "Geofluids",
    abstract = "Abstract Previous studies of the areal variation in heat flow in the National Petroleum Reserve Alaska (NPRA) support the existence of an active topographically driven regional fluid flow regime in this central part of the North Slope foreland basin. Drilling records and wireline logs for over 30 wells drilled in the NPRA provide additional field information, which can be used to further constrain interpretation of the pattern of regional flow of basinal waters within the NPRA. Hydraulic heads estimated from drilling mud weights show that ground water flow occurs generally from south to north, but with divergence to the north‐east and north‐west away from the central part of the NPRA towards coastal areas of elevated shallow heat flow. Salinities calculated from SP logs range from less than 1 g L −1, to marine values of 35 g L −1, to hypersaline values of over 150 g L −1. The entire upper sedimentary section to a depth of 2 km or more in the eastern part of the NPRA has been preferentially flushed with meteoric water through an area corresponding to the sandiest portion of the Nanushuk group. Deeper areas of low salinity occur within the Sadlerochit and Lisburne sections. The pattern of regional flow in the east is complicated, however, by the presence of a large mass of hypersaline water at depth. It is not known whether these brines are being displaced laterally and upward towards the discharge end of the basin or whether fresher waters are simply riding up over the top. Deep, hypersaline waters also occur in fault slices in the Brooks Range and have survived meteoric flushing. The brines were probably formed at the time of deposition of the Lisburne carbonates. The fluid flow regime to the west is different. Low‐salinity waters may be flowing northward underneath this section through the Ellesmerian section and discharging upward nearer the coast. However, sparse well log control severely limits what can be deduced about the details of flow paths in the central and western parts of the NPRA.",
    url = "https://doi.org/10.1111/j.1468-8115.2004.00079.x",
    doi = "10.1111/j.1468-8115.2004.00079.x",
    openalex = "W2117728827",
    references = "openalexw251474935"
}

Bulk oil composition is an important economic consideration of a petroleum resource assessment. Geological and geochemical interpretations from previous North Slope studies combined with recently acquired geochemical data are used to predict representative oil gravity (?API) and sulfur content (wt.% S) of the oil types for the 2002 U.S. Geological Survey resource assessment of the National Petroleum Reserve of Alaska (NPRA). The oil types are named after their respective source rock units and include Kuna-Lisburne, Shublik-Otuk, Kingak-Blankenship, and Pebble-GRZ-Torok. The composition of the oil (24?API, 1.6 wt.% S) in the South Barrow 12 well was selected as representative of Kuna-Lisburne oil. The average gravity and sulfur values (23?API and 1.6 wt.% S, respectively) of the Kuparuk field were selected to be representative of Shublik-Otuk oil type. The composition of the oil (39?API, 0.3 wt.% S) from the Alpine field discovery well (ARCO Bergschrund 1) was selected to be representative of Kingak-Blankenship oil. The oil composition (37?API, 0.1 wt.% S) of Tarn field was considered representative of the Pebble-GRZ-Torok oil type in NPRA.

@article{doi103133ofr03407,
    author = "Lillis, Paul G.",
    title = "Representative Bulk Composition of Oil Types for the 2002 U.S. Geological Survey Resource Assessment of National Petroleum Reserve in Alaska",
    year = "2004",
    journal = "Antarctica A Keystone in a Changing World",
    abstract = "Bulk oil composition is an important economic consideration of a petroleum resource assessment. Geological and geochemical interpretations from previous North Slope studies combined with recently acquired geochemical data are used to predict representative oil gravity (?API) and sulfur content (wt.\% S) of the oil types for the 2002 U.S. Geological Survey resource assessment of the National Petroleum Reserve of Alaska (NPRA). The oil types are named after their respective source rock units and include Kuna-Lisburne, Shublik-Otuk, Kingak-Blankenship, and Pebble-GRZ-Torok. The composition of the oil (24?API, 1.6 wt.\% S) in the South Barrow 12 well was selected as representative of Kuna-Lisburne oil. The average gravity and sulfur values (23?API and 1.6 wt.\% S, respectively) of the Kuparuk field were selected to be representative of Shublik-Otuk oil type. The composition of the oil (39?API, 0.3 wt.\% S) from the Alpine field discovery well (ARCO Bergschrund 1) was selected to be representative of Kingak-Blankenship oil. The oil composition (37?API, 0.1 wt.\% S) of Tarn field was considered representative of the Pebble-GRZ-Torok oil type in NPRA.",
    url = "https://doi.org/10.3133/ofr03407",
    doi = "10.3133/ofr03407",
    openalex = "W2155232591",
    references = "crossref1985petroleum, doi101016s014663800000187x, doi10130603b59b0c16d111d78645000102c1865d, doi10130603b5b6eb16d111d78645000102c1865d, doi10130603b5b6ff16d111d78645000102c1865d, doi1013062f91999f16ce11d78645000102c1865d, doi10130694887492170411d78645000102c1865d, doi101306m60585, doi101306st20445c1, openalexw2208838932, openalexw321081187"
}

@misc{binnian2005beaufort,
    author = "Binnian, Emily F.",
    title = "Beaufort Coastal Plain, North Slope, Alaska",
    year = "2005",
    booktitle = "Fact Sheet",
    url = "https://doi.org/10.3133/fs20053007",
    doi = "10.3133/fs20053007"
}

@article{s2c0017f9c80a9e23cf3789c465a56f5097ddb5d02,
    author = "Brandlen, Erik",
    title = "Poster Session Abstracts: Taxonomic Diagnosis of the Hadrosaur from the Liscomb Bone Bed, Prince Creek Formation, North Slope, Alaska - Abstract",
    year = "2005",
    url = "https://www.semanticscholar.org/paper/c0017f9c80a9e23cf3789c465a56f5097ddb5d02",
    is_oa = "true",
    openalex = "W2255314803",
    semanticscholar_id = "c0017f9c80a9e23cf3789c465a56f5097ddb5d02"
}

Fossils within accreted terranes are typically used to describe the age or origin of the exotic geologic blocks. However, accretion may also provide new pathways for faunal exchange between previously disconnected landmasses. One such landmass, the result of accretion, is Beringia, that entity encompassing northeastern Asia and northwestern North America and the surmised land connection between the two regions.

@incollection{doi101130200844215,
    author = "Fiorillo, Anthony R.",
    title = "Dinosaurs of Alaska: Implications for the Cretaceous origin of Beringia",
    year = "2008",
    booktitle = "Geological Society of America eBooks",
    abstract = "Fossils within accreted terranes are typically used to describe the age or origin of the exotic geologic blocks. However, accretion may also provide new pathways for faunal exchange between previously disconnected landmasses. One such landmass, the result of accretion, is Beringia, that entity encompassing northeastern Asia and northwestern North America and the surmised land connection between the two regions.",
    url = "https://doi.org/10.1130/2008.442(15)",
    doi = "10.1130/2008.442(15)",
    openalex = "W2345484674",
    references = "fiorillo2004the, openalexw2204429280"
}

@article{doi101016jmarpetgeo200910001,
    author = "Torres, Marta E. and Collett, Timothy S. and Rose, Kelly and Sample, James and Agena, W.F. and Rosenbaum, Eilis",
    title = "Pore fluid geochemistry from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope",
    year = "2009",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2009.10.001",
    doi = "10.1016/j.marpetgeo.2009.10.001",
    openalex = "W1996249396",
    references = "birdNonenorth, doi1010160016703753900519, doi101029gm124, doi101038nature04800, doi101038nature05043, doi101111j215334901964tb00181x, doi1012019781420008494, openalexw1591593323, openalexw2788326797, openalexw657177744"
}

Abstract Palaeozoic to early Mesozoic terranes of the North American Cordillera mostly originated from three distinct regions in Palaeozoic time: the western peri-Laurentian margin, western (Asian) Panthalassa, and the northern Caledonides–Siberia. A review of geological history, fossil and provenance data for the Caledonian–Siberian terranes suggests that they probably occupied an intermediate position between northern Baltica, northeastern Laurentia and Siberia, in proximity to the northern Caledonides, in early Palaeozoic time. Dispersion of these terranes and their westward incursion into eastern Panthalassa are interpreted to result from development of a Caribbean- or Scotia-style subduction system between northern Laurentia and Siberia in mid-Palaeozoic time, termed here the Northwest Passage. Westward propagation of a narrow subduction zone coupled with a global change in plate motion, related to the collision of Gondwana with Laurentia–Baltica, are proposed to have led to initiation of subduction along the western passive margin of Laurentia and development of the peri-Laurentian terranes as a set of rifted continental fragments, superimposed arcs and marginal ocean basin(s) in mid- to late Palaeozoic time. Diachronous orogenic activity from Late Silurian in Arctic Canada, to Early Devonian in north Yukon and adjacent Alaska, Middle Devonian in southeastern British Columbia, and Late Devonian–Early Mississippian in the western USA records progressive development of the Northwest Passage and southward propagation of subduction along western Laurentia.

@article{doi101144sp31810,
    author = "Colpron, Maurice and Nelson, JoAnne L.",
    title = "A Palaeozoic Northwest Passage: incursion of Caledonian, Baltican and Siberian terranes into eastern Panthalassa, and the early evolution of the North American Cordillera",
    year = "2009",
    journal = "Geological Society London Special Publications",
    abstract = "Abstract Palaeozoic to early Mesozoic terranes of the North American Cordillera mostly originated from three distinct regions in Palaeozoic time: the western peri-Laurentian margin, western (Asian) Panthalassa, and the northern Caledonides–Siberia. A review of geological history, fossil and provenance data for the Caledonian–Siberian terranes suggests that they probably occupied an intermediate position between northern Baltica, northeastern Laurentia and Siberia, in proximity to the northern Caledonides, in early Palaeozoic time. Dispersion of these terranes and their westward incursion into eastern Panthalassa are interpreted to result from development of a Caribbean- or Scotia-style subduction system between northern Laurentia and Siberia in mid-Palaeozoic time, termed here the Northwest Passage. Westward propagation of a narrow subduction zone coupled with a global change in plate motion, related to the collision of Gondwana with Laurentia–Baltica, are proposed to have led to initiation of subduction along the western passive margin of Laurentia and development of the peri-Laurentian terranes as a set of rifted continental fragments, superimposed arcs and marginal ocean basin(s) in mid- to late Palaeozoic time. Diachronous orogenic activity from Late Silurian in Arctic Canada, to Early Devonian in north Yukon and adjacent Alaska, Middle Devonian in southeastern British Columbia, and Late Devonian–Early Mississippian in the western USA records progressive development of the Northwest Passage and southward propagation of subduction along western Laurentia.",
    url = "https://doi.org/10.1144/sp318.10",
    doi = "10.1144/sp318.10",
    openalex = "W2102311915",
    references = "doi101017s0022336000019193, doi1010292005tc001830, doi101029tc006i006p00807, doi101130dnaggnac2171, doi101130dnaggnag149"
}

@article{doi101016jmarpetgeo201001008,
    author = "Winters, William J. and Walker, Michael and Hunter, Robert and Collett, Timothy S. and Boswell, Ray and Rose, Kelly and Waite, William F. and Torres, Marta E. and Patil, Shirish and Dandekar, Abhijit",
    title = "Physical properties of sediment from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope",
    year = "2010",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2010.01.008",
    doi = "10.1016/j.marpetgeo.2010.01.008",
    openalex = "W1985197515",
    references = "doi101016jmarpetgeo200910001"
}

@article{doi101016jmarpetgeo201001015,
    author = "Anderson, B. J. and Kurihara, Masanori and White, Mark D. and Moridis, George J. and Wilson, Scott and Pooladi‐Darvish, Mehran and Gaddipati, Manohar and Masuda, Yoshihiro and Collett, Timothy S. and Hunter, Robert and Narita, Hideo and Rose, Kelly and Boswell, Ray",
    title = "Regional long-term production modeling from a single well test, Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope",
    year = "2010",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2010.01.015",
    doi = "10.1016/j.marpetgeo.2010.01.015",
    openalex = "W2083009991",
    references = "doi101016jmarpetgeo200910001"
}

@article{doi101016jmarpetgeo201002001,
    author = "Rose, Kelly and Boswell, Ray and Collett, Timothy S.",
    title = "Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Coring operations, core sedimentology, and lithostratigraphy",
    year = "2010",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2010.02.001",
    doi = "10.1016/j.marpetgeo.2010.02.001",
    openalex = "W1969737096",
    references = "doi101016jmarpetgeo200910001"
}

@article{doi101016jmarpetgeo201002015,
    author = "Hunter, Robert and Collett, Timothy S. and Boswell, Ray and Anderson, B. J. and Digert, Scott A. and Pospisil, Gordon and Baker, Richard and Weeks, Micaela",
    title = "Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Overview of scientific and technical program",
    year = "2010",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2010.02.015",
    doi = "10.1016/j.marpetgeo.2010.02.015",
    openalex = "W2031589630",
    references = "doi101016jmarpetgeo200910001"
}

BACKGROUND: Basal iguanodontian dinosaurs were extremely successful animals, found in great abundance and diversity almost worldwide during the Early Cretaceous. In contrast to Europe and Asia, the North American record of Early Cretaceous basal iguanodonts has until recently been limited largely to skulls and skeletons of Tenontosaurus tilletti. METHODOLOGY/PRINCIPAL FINDINGS: Herein we describe two new basal iguanodonts from the Yellow Cat Member of the Cedar Mountain Formation of eastern Utah, each known from a partial skull and skeleton. Iguanacolossus fortis gen. et sp. nov. and Hippodraco scutodens gen. et sp. nov. are each diagnosed by a single autapomorphy and a unique combination of characters. CONCLUSIONS/SIGNIFICANCE: Iguanacolossus and Hippodraco add greatly to our knowledge of North American basal iguanodonts and prompt a new comprehensive phylogenetic analysis of basal iguanodont relationships. This analysis indicates that North American Early Cretaceous basal iguanodonts are more basal than their contemporaries in Europe and Asia.

@article{doi101371journalpone0014075,
    author = "McDonald, Andrew T. and Kirkland, James I. and DeBlieux, Donald D. and Madsen, Scott K. and Cavin, Jennifer and Milner, Andrew R. and Panzarin, Lukas",
    title = "New Basal Iguanodonts from the Cedar Mountain Formation of Utah and the Evolution of Thumb-Spiked Dinosaurs",
    year = "2010",
    journal = "PLoS ONE",
    abstract = "BACKGROUND: Basal iguanodontian dinosaurs were extremely successful animals, found in great abundance and diversity almost worldwide during the Early Cretaceous. In contrast to Europe and Asia, the North American record of Early Cretaceous basal iguanodonts has until recently been limited largely to skulls and skeletons of Tenontosaurus tilletti. METHODOLOGY/PRINCIPAL FINDINGS: Herein we describe two new basal iguanodonts from the Yellow Cat Member of the Cedar Mountain Formation of eastern Utah, each known from a partial skull and skeleton. Iguanacolossus fortis gen. et sp. nov. and Hippodraco scutodens gen. et sp. nov. are each diagnosed by a single autapomorphy and a unique combination of characters. CONCLUSIONS/SIGNIFICANCE: Iguanacolossus and Hippodraco add greatly to our knowledge of North American basal iguanodonts and prompt a new comprehensive phylogenetic analysis of basal iguanodont relationships. This analysis indicates that North American Early Cretaceous basal iguanodonts are more basal than their contemporaries in Europe and Asia.",
    url = "https://doi.org/10.1371/journal.pone.0014075",
    doi = "10.1371/journal.pone.0014075",
    openalex = "W2049267198",
    references = "doi101007s0011401006506, doi101016s1631068303000022, doi101017s1477201903001032, doi10103821872, doi10108002724634199810011101, doi101086407120, doi101098rspl18870117, doi101111j10960031200800217x, doi101111j10963642200900617x, doi102475ajss319111253, doi105860choice393984, olson1972stratigraphy, openalexw3215057009, openalexw597685939"
}

The late Campanian–Maastrichtian Liscomb Bonebed is the richest source of dinosaur remains thus far documented in the polar regions. This bed is formally defined herein and assigned to the upper part of the Prince Creek Formation; the bonebed and several other organic-rich beds are part of a 178 m sequence of fluvial and volcaniclastic deposits. The Liscomb Bonebed is a mudstone rich in clay, comminuted plant remains, and palynomorphs with a total organic carbon (TOC) of 6.80%–10.55%. It contains a multitaxic, low-diversity, dinosaur assemblage, dominated by Edmontosaurus sp., which is primarily represented by late juveniles. Four theropod taxa are almost exclusively represented by isolated teeth. With >6000 specimens collected, the assemblage is characterized by a Minimum Number of Individuals (MNI) of 36, dominance of Voorhies Groups I and II, and an underrepresentation of teeth, skulls, and girdles. Bones are highly fragmented and exhibit low weathering and abrasion indices. Bite marks occur on slightly more than 1% of elements. The densest accumulations of bone are typically found in the middle third of the bed with the largest bones at the bottom. The Liscomb Bonebed assemblage resulted from mass mortality associated with overbank floods that formed floodplain mires and ponds. Data from the current study clearly establish the Alaskan Arctic as the year-round residence of a rich dinosaur fauna and add further support to the hypotheses that even high-latitude hadrosaurids were gregarious and formed social groups.

@article{doi102110palo2009p09103r,
    author = "Gangloff, Roland A. and Fiorillo, Anthony R.",
    title = "TAPHONOMY AND PALEOECOLOGY OF A BONEBED FROM THE PRINCE CREEK FORMATION, NORTH SLOPE, ALASKA",
    year = "2010",
    journal = "Palaios",
    abstract = "The late Campanian–Maastrichtian Liscomb Bonebed is the richest source of dinosaur remains thus far documented in the polar regions. This bed is formally defined herein and assigned to the upper part of the Prince Creek Formation; the bonebed and several other organic-rich beds are part of a 178 m sequence of fluvial and volcaniclastic deposits. The Liscomb Bonebed is a mudstone rich in clay, comminuted plant remains, and palynomorphs with a total organic carbon (TOC) of 6.80\%–10.55\%. It contains a multitaxic, low-diversity, dinosaur assemblage, dominated by Edmontosaurus sp., which is primarily represented by late juveniles. Four theropod taxa are almost exclusively represented by isolated teeth. With >6000 specimens collected, the assemblage is characterized by a Minimum Number of Individuals (MNI) of 36, dominance of Voorhies Groups I and II, and an underrepresentation of teeth, skulls, and girdles. Bones are highly fragmented and exhibit low weathering and abrasion indices. Bite marks occur on slightly more than 1\% of elements. The densest accumulations of bone are typically found in the middle third of the bed with the largest bones at the bottom. The Liscomb Bonebed assemblage resulted from mass mortality associated with overbank floods that formed floodplain mires and ponds. Data from the current study clearly establish the Alaskan Arctic as the year-round residence of a rich dinosaur fauna and add further support to the hypotheses that even high-latitude hadrosaurids were gregarious and formed social groups.",
    url = "https://doi.org/10.2110/palo.2009.p09-103r",
    doi = "10.2110/palo.2009.p09-103r",
    openalex = "W2100240151",
    references = "doi101017cbo9780511536045, doi101017s0022336000018862, doi101017s0094837300005820, doi101666080251, doi102113gsrocky8specialpaper11, doi102307281081, doi105860choice300309, doi105860choice353642, doi105860choice393984, fiorillo2004the, openalexw158108064, openalexw2183707334, openalexw2989049194"
}

We report a likely neoceratopsian manus track from an exposure of the Nanushuk Formation along the Colville River in northern Alaska. The track described here containts the impressions of five digits, arranged as an arc, which identify this specimen as a manus. Details of the impression suggest that it is neoceratopsian rather than ankylosaurian. The length of the chord of the arc of the track is approximately 25 cm, which is half the size of manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops. The Nanushuk Formation is a succession of complexly intertonguing marine and nonmarine strata interpreted as shelf, deltaic, strandplain, fluvial, and alluvial overbank deposits. Deposited in the foreland basin north f the Brooks Range, the rock unit is present throughout most of the northern foothills belt and subsurface of the central and western North Slope coastal plain. Fossil and radiometric data place outcrop within the Albian. If the identification of the track is correct, this is one of the earlies occurrences of neoceratopsians from North America. The occurrence of this track in Alaska substantiates the biogeographic model of faunal exchange between Asia and North America through a Cretaceous land bridge known as Beringia.

@article{doi105209jige33853,
    author = "Fiorillo, Anthony R. and Decker, P. L. and LePain, David L. and Wartes, M. A. and McCarthy, Paul J.",
    title = "A Probable Neoceratopsian Manus Track from the Nanushuk Formation (Albian, Northern Alaska)",
    year = "2010",
    journal = "Complutensian Scientific Journals (Complutense University of Madrid)",
    abstract = "We report a likely neoceratopsian manus track from an exposure of the Nanushuk Formation along the Colville River in northern Alaska. The track described here containts the impressions of five digits, arranged as an arc, which identify this specimen as a manus. Details of the impression suggest that it is neoceratopsian rather than ankylosaurian. The length of the chord of the arc of the track is approximately 25 cm, which is half the size of manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops. The Nanushuk Formation is a succession of complexly intertonguing marine and nonmarine strata interpreted as shelf, deltaic, strandplain, fluvial, and alluvial overbank deposits. Deposited in the foreland basin north f the Brooks Range, the rock unit is present throughout most of the northern foothills belt and subsurface of the central and western North Slope coastal plain. Fossil and radiometric data place outcrop within the Albian. If the identification of the track is correct, this is one of the earlies occurrences of neoceratopsians from North America. The occurrence of this track in Alaska substantiates the biogeographic model of faunal exchange between Asia and North America through a Cretaceous land bridge known as Beringia.",
    url = "https://doi.org/10.5209/jige.33853",
    doi = "10.5209/jige.33853",
    openalex = "W2108835938",
    references = "openalexw2204429280"
}

We report a likely neoceratopsian manus track from an exposure of the Nanushuk Formation along the Colville River in northern Alaska. The track described here containts the impressions of five digits, arranged as an arc, which identify this specimen as a manus. Details of the impression suggest that it is neoceratopsian rather than ankylosaurian. The length of the chord of the arc of the track is approximately 25 cm, which is half the size of manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops. The Nanushuk Formation is a succession of complexly intertonguing marine and nonmarine strata interpreted as shelf, deltaic, strandplain, fluvial, and alluvial overbank deposits. Deposited in the foreland basin north f the Brooks Range, the rock unit is present throughout most of the northern foothills belt and subsurface of the central and western North Slope coastal plain. Fossil and radiometric data place outcrop within the Albian. If the identification of the track is correct, this is one of the earlies occurrences of neoceratopsians from North America. The occurrence of this track in Alaska substantiates the biogeographic model of faunal exchange between Asia and North America through a Cretaceous land bridge known as Beringia.

@article{doi105209revjige2010v36n24,
    author = "Fiorillo, Anthony R. and Decker, P. L. and LePain, David L. and Wartes, M. A. and McCarthy, Paul J.",
    title = "A Probable Neoceratopsian Manus Track from the Nanushuk Formation (Albian, Northern Alaska)",
    year = "2010",
    journal = "Journal of Iberian Geology",
    abstract = "We report a likely neoceratopsian manus track from an exposure of the Nanushuk Formation along the Colville River in northern Alaska. The track described here containts the impressions of five digits, arranged as an arc, which identify this specimen as a manus. Details of the impression suggest that it is neoceratopsian rather than ankylosaurian. The length of the chord of the arc of the track is approximately 25 cm, which is half the size of manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops. The Nanushuk Formation is a succession of complexly intertonguing marine and nonmarine strata interpreted as shelf, deltaic, strandplain, fluvial, and alluvial overbank deposits. Deposited in the foreland basin north f the Brooks Range, the rock unit is present throughout most of the northern foothills belt and subsurface of the central and western North Slope coastal plain. Fossil and radiometric data place outcrop within the Albian. If the identification of the track is correct, this is one of the earlies occurrences of neoceratopsians from North America. The occurrence of this track in Alaska substantiates the biogeographic model of faunal exchange between Asia and North America through a Cretaceous land bridge known as Beringia.",
    url = "https://doi.org/10.5209/rev\_jige.2010.v36.n2.4",
    doi = "10.5209/rev\_jige.2010.v36.n2.4",
    openalex = "W2328800625",
    references = "openalexw2204429280"
}

@article{doi101080089129632010546856,
    author = "Erickson, G. and Druckenmiller, P.",
    title = "Longevity and growth rate estimates for a polar dinosaur: a Pachyrhinosaurus (Dinosauria: Neoceratopsia) specimen from the North Slope of Alaska showing a complete developmental record",
    year = "2011",
    journal = "Historical Biology",
    url = "https://www.semanticscholar.org/paper/5e744776322cdd95a52290a1530f4aaee1a348b7",
    doi = "10.1080/08912963.2010.546856",
    is_oa = "true",
    number = "4",
    pages = "327-334",
    semanticscholar_citation_count = "37",
    semanticscholar_id = "5e744776322cdd95a52290a1530f4aaee1a348b7",
    volume = "23"
}

The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal Cretaceous extinction event. Hadrosaurine hadrosaurids (Dinosauria: Ornithopoda) closely related to Edmontosaurus are among the most common megaherbivores in latest Campanian and Maastrichtian deposits of western North America. However, interpretations of edmontosaur species richness and biostratigraphy have been in constant flux for almost three decades, although the clade is generally thought to have undergone a radiation in the late Maastrichtian. We address the issue of edmontosaur diversity for the first time using rigorous morphometric analyses of virtually all known complete edmontosaur skulls. Results suggest only two valid species, Edmontosaurus regalis from the late Campanian, and E. annectens from the late Maastrichtian, with previously named taxa, including the controversial Anatotitan copei, erected on hypothesized transitional morphologies associated with ontogenetic size increase and allometric growth. A revision of North American hadrosaurid taxa suggests a decrease in both hadrosaurid diversity and disparity from the early to late Maastrichtian, a pattern likely also present in ceratopsid dinosaurs. A decline in the disparity of dominant megaherbivores in the latest Maastrichtian interval supports the hypothesis that dinosaur diversity decreased immediately preceding the end Cretaceous extinction event.

@article{doi101371journalpone0025186,
    author = "Campione, Nicolás E. and Evans, David C.",
    title = "Cranial Growth and Variation in Edmontosaurs (Dinosauria: Hadrosauridae): Implications for Latest Cretaceous Megaherbivore Diversity in North America",
    year = "2011",
    journal = "PLoS ONE",
    abstract = "The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal Cretaceous extinction event. Hadrosaurine hadrosaurids (Dinosauria: Ornithopoda) closely related to Edmontosaurus are among the most common megaherbivores in latest Campanian and Maastrichtian deposits of western North America. However, interpretations of edmontosaur species richness and biostratigraphy have been in constant flux for almost three decades, although the clade is generally thought to have undergone a radiation in the late Maastrichtian. We address the issue of edmontosaur diversity for the first time using rigorous morphometric analyses of virtually all known complete edmontosaur skulls. Results suggest only two valid species, Edmontosaurus regalis from the late Campanian, and E. annectens from the late Maastrichtian, with previously named taxa, including the controversial Anatotitan copei, erected on hypothesized transitional morphologies associated with ontogenetic size increase and allometric growth. A revision of North American hadrosaurid taxa suggests a decrease in both hadrosaurid diversity and disparity from the early to late Maastrichtian, a pattern likely also present in ceratopsid dinosaurs. A decline in the disparity of dominant megaherbivores in the latest Maastrichtian interval supports the hypothesis that dinosaur diversity decreased immediately preceding the end Cretaceous extinction event.",
    url = "https://doi.org/10.1371/journal.pone.0025186",
    doi = "10.1371/journal.pone.0025186",
    openalex = "W2153077072",
    references = "doi101016b9780127784601x50005, doi101017s0094837300014056, doi101038277560a0, doi101038358059a0, doi101080027246342010483632, doi101080089129632012688589, doi101093bioinformaticsbtg287, doi101093bioinformaticsbtm069, doi101093sysbio24137, doi101098rspb20090352, doi101098rspl18870117, doi101111j10963642200400130x, doi101111j10963642200900617x, doi101130spe40p1, doi101371journalpone0007626, doi102110palo2009p09103r, doi1023071005355, doi102475ajss319111253, gilmore1924a, russell2002synopsis, sloan1986gradual"
}

Fiorillo, Anthony R., Tykoski, Ronald S. (2012): A new Maastrichtian species of the centrosaurine ceratopsid Pachyrhinosaurus from the North Slope of Alaska. Acta Palaeontologica Polonica 57 (3): 561-573, DOI: 10.4202/app.2011.0033, URL: http://dx.doi.org/10.4202/app.2011.0033

@article{doi104202app20110033,
    author = "Fiorillo, Anthony R. and Tykoski, Ronald S.",
    title = "A New Maastrichtian Species of the Centrosaurine Ceratopsid Pachyrhinosaurus from the North Slope of Alaska",
    year = "2011",
    journal = "Acta Palaeontologica Polonica",
    abstract = "Fiorillo, Anthony R., Tykoski, Ronald S. (2012): A new Maastrichtian species of the centrosaurine ceratopsid Pachyrhinosaurus from the North Slope of Alaska. Acta Palaeontologica Polonica 57 (3): 561-573, DOI: 10.4202/app.2011.0033, URL: http://dx.doi.org/10.4202/app.2011.0033",
    url = "https://doi.org/10.4202/app.2011.0033",
    doi = "10.4202/app.2011.0033",
    openalex = "W2117212210",
    references = "davies1987duckbill, doi101111j109636421997tb00340x, doi101126science13334591105, doi1011300813723604333, doi101130dnaggnal593, doi1011399780660198194, doi101139e05029, doi1016690883135120010160482ttoaco20co2, doi102110palo2009p09103r, doi105860choice361591, doi105962bhlpart22969, fiorillo2004the, openalexw2105264054, parrish1987late"
}

On the Arctic Coastal Plain of the National Petroleum Reserve-Alaska (NPR-A), the Teshekpuk Lake Special Area (TLSA) was recognized to protect outstanding wildlife values. Although information has accumulated on the TLSA’s value to caribou and waterfowl, its importance to breeding shorebirds remains largely unquantified. Therefore, we undertook a broad-scale ground study to estimate the population size and density of shorebirds breeding in the TLSA. From a series of plot surveys conducted from 2006 to 2008, we estimated a detection-adjusted total breeding population of more than 573 000 shorebirds and an overall density of 126 shorebirds/km2. Most shorebird species had their greatest densities on the Outer Coastal Plain or had approximately equal densities on Outer and Inner Coastal Plains; only two species had their greatest densities on the Inner Coastal Plain. The greatest densities of breeding shorebirds occurred immediately around Teshekpuk Lake. The TLSA supported more than 10% of the biogeographic populations of black-bellied plover (Pluvialis squatarola), semipalmated sandpiper (Calidris pusilla), and dunlin (C. alpina). Breeding shorebird density in the TLSA is one of the highest in the NPR-A, on Alaska’s North Slope, and throughout the circumpolar Arctic. Our results, coupled with previous information on waterfowl and caribou, indicate that the area around Teshekpuk Lake and the recognized goose molting area northeast of the lake should be protected from oil and gas development.

@article{doi1014430arctic4239,
    author = "Andres, Brad A. and Johnson, James A. and Brown, Stephen C. and Lanctot, Richard B.",
    title = "Shorebirds Breed in Unusually High Densities in the Teshekpuk Lake Special Area, Alaska",
    year = "2012",
    journal = "ARCTIC",
    abstract = "On the Arctic Coastal Plain of the National Petroleum Reserve-Alaska (NPR-A), the Teshekpuk Lake Special Area (TLSA) was recognized to protect outstanding wildlife values. Although information has accumulated on the TLSA’s value to caribou and waterfowl, its importance to breeding shorebirds remains largely unquantified. Therefore, we undertook a broad-scale ground study to estimate the population size and density of shorebirds breeding in the TLSA. From a series of plot surveys conducted from 2006 to 2008, we estimated a detection-adjusted total breeding population of more than 573 000 shorebirds and an overall density of 126 shorebirds/km2. Most shorebird species had their greatest densities on the Outer Coastal Plain or had approximately equal densities on Outer and Inner Coastal Plains; only two species had their greatest densities on the Inner Coastal Plain. The greatest densities of breeding shorebirds occurred immediately around Teshekpuk Lake. The TLSA supported more than 10\% of the biogeographic populations of black-bellied plover (Pluvialis squatarola), semipalmated sandpiper (Calidris pusilla), and dunlin (C. alpina). Breeding shorebird density in the TLSA is one of the highest in the NPR-A, on Alaska’s North Slope, and throughout the circumpolar Arctic. Our results, coupled with previous information on waterfowl and caribou, indicate that the area around Teshekpuk Lake and the recognized goose molting area northeast of the lake should be protected from oil and gas development.",
    url = "https://doi.org/10.14430/arctic4239",
    doi = "10.14430/arctic4239",
    openalex = "W1972389230",
    references = "birdNonenorth, doi1010079780387217062, doi101007s0026500408252, doi10164100063568200656801sceabs20co2, doi1016420004803820021190036dsteda20co2, doi101722610639, doi1018900816611, doi1018901051076119970070218eordos20co2, doi107146mogbiosciv59142631, openalexw1520995987, openalexw1858804344"
}

We report on the first record of a therizinosaur from Alaska. This record consists of a single pes track from the lower part of the Upper Cretaceous Cantwell Formation in Denali National Park, Alaska, United States. This is the northernmost occurrence for this group of dinosaurs, and the presence of this animal in Alaska offers the first support of the proposed biogeographic model of faunal exchange during the Cretaceous for these unusual theropods.

@article{doi102110palo2011p11083r,
    author = "Fiorillo, Anthony R. and Adams, Thomas L.",
    title = "A THERIZINOSAUR TRACK FROM THE LOWER CANTWELL FORMATION (UPPER CRETACEOUS) OF DENALI NATIONAL PARK, ALASKA",
    year = "2012",
    journal = "Palaios",
    abstract = "We report on the first record of a therizinosaur from Alaska. This record consists of a single pes track from the lower part of the Upper Cretaceous Cantwell Formation in Denali National Park, Alaska, United States. This is the northernmost occurrence for this group of dinosaurs, and the presence of this animal in Alaska offers the first support of the proposed biogeographic model of faunal exchange during the Cretaceous for these unusual theropods.",
    url = "https://doi.org/10.2110/palo.2011.p11-083r",
    doi = "10.2110/palo.2011.p11-083r",
    openalex = "W2111648643",
    references = "openalexw2204429280"
}

PREFACE: James O. Farlow and M. K. Brett-Surman PART ONE: THE DISCOVERY OF DINOSAURS The Earliest Discoveries: William A. S. Sarjeant European Dinosaur Hunters: Hans-Dieter Sues North American Dinosaur Hunters: Edwin H. Colbert Asian Dinosaur Hunters: John R. Lavas Dinosaur Hunters of the Southern Continents: Thomas R. Holtz, Jr. PART TWO: THE STUDY OF DINOSAURS Hunting for Dinosaur Bones: David D. Gillette The Osteology of the Dinosaurs: Thomas R. Holtz, Jr. and M. K.Brett-Surman The Taxonomy and Systematics of the Dinosaurs: Thomas R. Holtz, Jr. and M. K. Brett-Surman Dinosaurs and Geologic Time: James O. Farlow The Scientific Study of Dinosaurs: Ralph E. Chapman Molecular Paleontology: Rationale and Techniques for the Study of Ancient Biomolecules: Mary Higby Schweitzer Dinosaurs as Museum Exhibits: Kenneth Carpenter Restoring Dinosaurs as Living Animals: Douglas Henderson PART THREE: THE GROUPS OF DINOSAURS Introduction: James O. Farlow and M. K. Brett-Surman Politics and Paleontology: Richard Owen and the Invention of Dinosaurs: Hugh Torrens Evolution of the Archosaurs: J. Michael Parrish Origin and Early Evolution of Dinosaurs: Michael J. Benton Theropods: Philip J. Currie Segnosaurs (Therezinosaurs): Teresa Maryanska Prosauropods: Jacques VanHeerden Sauropods: John S. McIntosh, M. K. Brett-Surman, and James O. Farlow Stegosaurs: Peter M. Galton Ankylosaurs: Kenneth Carpenter Marginocephalians: Catherine A. Forster and Paul C. Sereno Ornithopods: M. K. Brett-Surman PART FOUR: BIOLOGY OF THE DINOSAURS Land Plants as Food and Habitat in the Age of Dinosaurs: Bruce H. Tiffney What Did Dinosaurs Eat? Coprolites and Other Direct Evidence of Dinosaur Diets: Karen Chin Dinosaur Combat and Courtship: Scott Sampson Dinosaur Eggs: Karl F. Hirsch and Darla K. Zelenitsky How Dinosaurs Grew: R. E. H. Reid Engineering a Dinosaur: R. McN. Alexander Dinosaurian Paleopathology: Bruce M. Rothschild Dinosaurian Physiology: the Case for Intermediate Dinosaurs: R. E. H. Reid Oxygen Isotopes in Dinosaur Bone: Reese E. Barrick, Michael K. Stoskopf, and William J. Showers A Blueprint for Giants: Do Living Reptiles, Birds or Mammals Provide the Best Model for the Physiology of Large Dinosaurs? Frank V. Paladino, James R. Spotila, and Peter Dodson New Insights into the Metabolic Physiology of Dinosaurs: John Ruben, Andrew Leitch, Willem Hillenius, Nicholas Geist, and Terry Jones The Scientific Study of Dinosaur Footprints: James O. Farlow and Ralph E. Chapman The Paleoecological and Paleoenvironmental Utility of Dinosaur Tracks: Martin G. Lockley PART FIVE: DINOSAUR EVOLUTION IN THE CHANGING WORLD OF THE MESOZOIC ERA Biogeography for Dinosaurs: Ralph E. Molnar Major Groups of Non-Dinosaurian Vertebrates of the Mesozoic Era: Michael Morales Continental Tetrapods of the Early Mesozoic: Faunas and Faunal Changes: Hans-Dieter Sues Dinosaurian Faunas of the Later Mesozoic: Dale A. Russell and Jose F. Bonaparte The Extinction of the Dinosaurs: A Dialogue Between a Catastrophist and a Gradualist: Dale A. Russell and Peter Dodson PART SIX: DINOSAURS AND THE MEDIA Dinosaurs and the Media: Donald F. Glut and M. K. Brett-Surman APPENDIX: A CHRONOLOGICAL HISTORY OF DINOSAUR PALEONTOLOGY: M. K. Brett-Surman GLOSSARY CONTRIBUTORS INDEX

@book{openalexw1585246501,
    author = "Farlow, James O. and Brett-Surman, Michael K.",
    title = "The Complete Dinosaur",
    year = "2012",
    booktitle = "Opus: Research \& Creativity (Indiana University – Purdue University Fort Wayne)",
    abstract = "PREFACE: James O. Farlow and M. K. Brett-Surman PART ONE: THE DISCOVERY OF DINOSAURS The Earliest Discoveries: William A. S. Sarjeant European Dinosaur Hunters: Hans-Dieter Sues North American Dinosaur Hunters: Edwin H. Colbert Asian Dinosaur Hunters: John R. Lavas Dinosaur Hunters of the Southern Continents: Thomas R. Holtz, Jr. PART TWO: THE STUDY OF DINOSAURS Hunting for Dinosaur Bones: David D. Gillette The Osteology of the Dinosaurs: Thomas R. Holtz, Jr. and M. K.Brett-Surman The Taxonomy and Systematics of the Dinosaurs: Thomas R. Holtz, Jr. and M. K. Brett-Surman Dinosaurs and Geologic Time: James O. Farlow The Scientific Study of Dinosaurs: Ralph E. Chapman Molecular Paleontology: Rationale and Techniques for the Study of Ancient Biomolecules: Mary Higby Schweitzer Dinosaurs as Museum Exhibits: Kenneth Carpenter Restoring Dinosaurs as Living Animals: Douglas Henderson PART THREE: THE GROUPS OF DINOSAURS Introduction: James O. Farlow and M. K. Brett-Surman Politics and Paleontology: Richard Owen and the Invention of Dinosaurs: Hugh Torrens Evolution of the Archosaurs: J. Michael Parrish Origin and Early Evolution of Dinosaurs: Michael J. Benton Theropods: Philip J. Currie Segnosaurs (Therezinosaurs): Teresa Maryanska Prosauropods: Jacques VanHeerden Sauropods: John S. McIntosh, M. K. Brett-Surman, and James O. Farlow Stegosaurs: Peter M. Galton Ankylosaurs: Kenneth Carpenter Marginocephalians: Catherine A. Forster and Paul C. Sereno Ornithopods: M. K. Brett-Surman PART FOUR: BIOLOGY OF THE DINOSAURS Land Plants as Food and Habitat in the Age of Dinosaurs: Bruce H. Tiffney What Did Dinosaurs Eat? Coprolites and Other Direct Evidence of Dinosaur Diets: Karen Chin Dinosaur Combat and Courtship: Scott Sampson Dinosaur Eggs: Karl F. Hirsch and Darla K. Zelenitsky How Dinosaurs Grew: R. E. H. Reid Engineering a Dinosaur: R. McN. Alexander Dinosaurian Paleopathology: Bruce M. Rothschild Dinosaurian Physiology: the Case for Intermediate Dinosaurs: R. E. H. Reid Oxygen Isotopes in Dinosaur Bone: Reese E. Barrick, Michael K. Stoskopf, and William J. Showers A Blueprint for Giants: Do Living Reptiles, Birds or Mammals Provide the Best Model for the Physiology of Large Dinosaurs? Frank V. Paladino, James R. Spotila, and Peter Dodson New Insights into the Metabolic Physiology of Dinosaurs: John Ruben, Andrew Leitch, Willem Hillenius, Nicholas Geist, and Terry Jones The Scientific Study of Dinosaur Footprints: James O. Farlow and Ralph E. Chapman The Paleoecological and Paleoenvironmental Utility of Dinosaur Tracks: Martin G. Lockley PART FIVE: DINOSAUR EVOLUTION IN THE CHANGING WORLD OF THE MESOZOIC ERA Biogeography for Dinosaurs: Ralph E. Molnar Major Groups of Non-Dinosaurian Vertebrates of the Mesozoic Era: Michael Morales Continental Tetrapods of the Early Mesozoic: Faunas and Faunal Changes: Hans-Dieter Sues Dinosaurian Faunas of the Later Mesozoic: Dale A. Russell and Jose F. Bonaparte The Extinction of the Dinosaurs: A Dialogue Between a Catastrophist and a Gradualist: Dale A. Russell and Peter Dodson PART SIX: DINOSAURS AND THE MEDIA Dinosaurs and the Media: Donald F. Glut and M. K. Brett-Surman APPENDIX: A CHRONOLOGICAL HISTORY OF DINOSAUR PALEONTOLOGY: M. K. Brett-Surman GLOSSARY CONTRIBUTORS INDEX",
    openalex = "W1585246501",
    references = "chatterjee2013a, chinsamy1998polar, deklerk2000a, doi101002ar20982, doi101002ara10097, doi101002jmor10406, doi101007s0011400804883, doi1010160031018291900605, doi1010160034666781900695, doi101016jannpal200803002, doi101016jepsl200801015, doi101016jpalaeo201002025, doi101017cbo9780511608551, doi101017s0022336000018862, doi101017s0094837300007557, doi101017s0094837300016900, doi101017s0094837300021321, doi101038262207a0, doi101038307360a0, doi10103832884, doi101038359117a0, doi101038362709a0, doi101038368196a0, doi101038nature03635, doi101038nature10906, doi101046j14401738200300386x, doi10108002724634199810011086, doi10108002724634199910011125, doi10108008912960903503345, doi10108010420940802471027, doi101086284406, doi101086422766, doi101098rspb20060443, doi101111j10963642200600245x, doi101111j10963642200900631x, doi101111j1469185x200900107x, doi101111j150239311985tb00690x, doi101111j15023931200900187x, doi101126science1157704, doi101126science1180219, doi101126science172397867, doi101126science24248841403, doi101126science27352791204, doi101127njgpm19831983141, doi1011300091761319930210503pioatv23co2, doi101130g23452a1, doi101130spe40p1, doi101144001676492006032, doi101144gslsp20042280106, doi101146annurevearth040610133502, doi101146annurevearth28119, doi101146annurevgenet37110801143214, doi10120600030082200635301ydanpc20co2, doi1012066391, doi101353book59141, doi101371journalpone0012292, doi1016660094837320000260450fpindi20co2, doi1016660094837320050310291teafot20co2, doi1016690883135120030180286rpoumt20co2, doi1016710272463420020220593cvancf20co2, doi1016710272463420020220766tehits20co2, doi101671a11168, doi102110palo2007p07070r, doi1023071445147, doi1023073514548, doi102475ajss425149387, doi104202app20080049, doi105281zenodo13315375, doi105281zenodo16692311, doi105281zenodo3739898, doi105962p339375, fiorillo2004the, jacobsen1998feeding, lehman1987late, nelson1980counts, openalexw1550095290, openalexw1558456135, openalexw2163397885, openalexw2242116350, openalexw2506868775, pontzer2009biomechanics, russell2002synopsis, seymour1976dinosaurs, sloan1986gradual, stevens2006binocular, witmer1991biomechanics, woodward1910on"
}

We used data from aerial surveys (1992-2010) of >100,000 km(2) and ground surveys (1998-2004) of >150 km(2) to estimate the density and abundance of birds on the North Slope of Alaska (U.S.A.). In the ground surveys, we used double sampling to estimate detection ratios. We used the aerial survey data to compare densities of birds and Arctic fox (Vulpes lagopus), the major nest predator of birds, on the North Slope, in Prudhoe Bay, and in nearby areas. We partitioned the Prudhoe Bay oil field into 2 × 2 km plots and determined the relation between density of aquatic birds and density of roads, buildings, and other infrastructure in these plots. Abundance and density (birds per square kilometer) of 3 groups of aquatic birds-waterfowl, loons, and grebes; shorebirds; and gulls, terns, and jaegers-were highest in the National Petroleum Reserve-Alaska (NPRA) and lowest in the Arctic National Wildlife Refuge. Six other major wetlands occur in the Arctic regions of Canada and Russia, but the largest population of aquatic birds was in the NPRA. Aquatic birds were concentrated in the northern part of the NPRA. For example, an area that covered 18% of the NPRA included 53% of its aquatic birds. The aerial surveys showed that bird density was not lower and fox density was not higher in Prudhoe Bay than in surrounding areas. Density of infrastructure did not significantly affect bird density for any group of species. Our results establish that the NPRA is one of the most important areas for aquatic birds in the Arctic. Our results and those of others also indicate that oil production, as practiced in Prudhoe Bay, does not necessarily lead to substantial declines in bird density or productivity in or near the developed areas. Prioridades para la Conservación de Aves en el Norte de Alaska.

@article{doi101111cobi12133,
    author = "Bart, Jonathan and Platte, Robert M. and Andres, Brad A. and Brown, Stephen C. and Johnson, James A. and Larned, William W.",
    title = "Importance of the National Petroleum Reserve–Alaska for Aquatic Birds",
    year = "2013",
    journal = "Conservation Biology",
    abstract = "We used data from aerial surveys (1992-2010) of >100,000 km(2) and ground surveys (1998-2004) of >150 km(2) to estimate the density and abundance of birds on the North Slope of Alaska (U.S.A.). In the ground surveys, we used double sampling to estimate detection ratios. We used the aerial survey data to compare densities of birds and Arctic fox (Vulpes lagopus), the major nest predator of birds, on the North Slope, in Prudhoe Bay, and in nearby areas. We partitioned the Prudhoe Bay oil field into 2 × 2 km plots and determined the relation between density of aquatic birds and density of roads, buildings, and other infrastructure in these plots. Abundance and density (birds per square kilometer) of 3 groups of aquatic birds-waterfowl, loons, and grebes; shorebirds; and gulls, terns, and jaegers-were highest in the National Petroleum Reserve-Alaska (NPRA) and lowest in the Arctic National Wildlife Refuge. Six other major wetlands occur in the Arctic regions of Canada and Russia, but the largest population of aquatic birds was in the NPRA. Aquatic birds were concentrated in the northern part of the NPRA. For example, an area that covered 18\% of the NPRA included 53\% of its aquatic birds. The aerial surveys showed that bird density was not lower and fox density was not higher in Prudhoe Bay than in surrounding areas. Density of infrastructure did not significantly affect bird density for any group of species. Our results establish that the NPRA is one of the most important areas for aquatic birds in the Arctic. Our results and those of others also indicate that oil production, as practiced in Prudhoe Bay, does not necessarily lead to substantial declines in bird density or productivity in or near the developed areas. Prioridades para la Conservación de Aves en el Norte de Alaska.",
    url = "https://doi.org/10.1111/cobi.12133",
    doi = "10.1111/cobi.12133",
    openalex = "W1900821284",
    references = "doi1014430arctic4239"
}

A paleontological reconnaissance survey on Cretaceous and Tertiary terrestrial units along the Yukon River drainage through much of east-central Alaska has provided new chronostratigraphic constraints for the units, paleoclimatological data, and the first information on the local biodiversity within an ancient, high latitude ecosystem. The studied unnamed rock unit is most notable for its historic economic gold placer deposits but our survey documents its relevance as a source-rock for Mesozoic terrestrial vertebrates, invertebrates and associated flora. Specifically, new U-Pb ages from detrital zircons combined with ichnological data are indicative of a Late Cretaceous age for at least the lower section of the studied rock unit, previously considered to be representative of nearly exclusively Tertiary deposition. Further, the results of our survey show that this sedimentary rock unit preserves the first record of dinosaurs in the vast east-central Alaska region. Lastly, paleobotanical data when compared to correlative rock units support previous interpretation that the Late Cretaceous continental ecosystem of Alaska was heterogeneous in nature and seasonal.

@article{doi102110palo2013054,
    author = "Fiorillo, Anthony R. and Fanti, Federico and Hults, Chad P. and Hasiotis, Stephen T.",
    title = "NEW ICHNOLOGICAL, PALEOBOTANICAL, AND DETRITAL ZIRCON DATA FROM AN UNNAMED ROCK UNIT IN YUKON-CHARLEY RIVERS NATIONAL PRESERVE (CRETACEOUS: ALASKA): STRATIGRAPHIC IMPLICATIONS FOR THE REGION",
    year = "2014",
    journal = "Palaios",
    abstract = "A paleontological reconnaissance survey on Cretaceous and Tertiary terrestrial units along the Yukon River drainage through much of east-central Alaska has provided new chronostratigraphic constraints for the units, paleoclimatological data, and the first information on the local biodiversity within an ancient, high latitude ecosystem. The studied unnamed rock unit is most notable for its historic economic gold placer deposits but our survey documents its relevance as a source-rock for Mesozoic terrestrial vertebrates, invertebrates and associated flora. Specifically, new U-Pb ages from detrital zircons combined with ichnological data are indicative of a Late Cretaceous age for at least the lower section of the studied rock unit, previously considered to be representative of nearly exclusively Tertiary deposition. Further, the results of our survey show that this sedimentary rock unit preserves the first record of dinosaurs in the vast east-central Alaska region. Lastly, paleobotanical data when compared to correlative rock units support previous interpretation that the Late Cretaceous continental ecosystem of Alaska was heterogeneous in nature and seasonal.",
    url = "https://doi.org/10.2110/palo.2013.054",
    doi = "10.2110/palo.2013.054",
    openalex = "W2153385453",
    references = "fiorillo2004the, openalexw2204429280"
}

@article{doi101016jcretres201504008,
    author = "Shimer, Grant and Benowitz, Jeffrey A. and Layer, Paul W. and McCarthy, Paul J. and Hanks, Catherine L. and Wartes, M. A.",
    title = "40Ar/39Ar ages and geochemical characterization of Cretaceous bentonites in the Nanushuk, Seabee, Tuluvak, and Schrader Bluff formations, North Slope, Alaska",
    year = "2015",
    journal = "Cretaceous Research",
    url = "https://doi.org/10.1016/j.cretres.2015.04.008",
    doi = "10.1016/j.cretres.2015.04.008",
    openalex = "W2179354420",
    references = "openalexw251474935"
}

You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.

@incollection{doi101130dnaggnag117,
    author = "Grantz, Arthur and May, Steve D. and Hart, Patrick E.",
    title = "Geology of the Arctic continental margin of Alaska",
    year = "2015",
    booktitle = "Geological Society of America eBooks",
    abstract = "You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.",
    url = "https://doi.org/10.1130/dnag-gna-g1.17",
    doi = "10.1130/dnag-gna-g1.17",
    openalex = "W2476760881",
    references = "mickey1985jurassicneocomian"
}

You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.

@incollection{doi101130dnaggnag1205,
    author = "Foster, Helen Laura and Keith, Terry E.C. and Menzie, W. David",
    title = "Geology of the Yukon-Tanana area of east-central Alaska",
    year = "2015",
    booktitle = "Geological Society of America eBooks",
    abstract = "You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.",
    url = "https://doi.org/10.1130/dnag-gna-g1.205",
    doi = "10.1130/dnag-gna-g1.205",
    openalex = "W2497538528",
    references = "doi103133cir967"
}

South-central Alaska is defined as the region bounded by the Kuskokwim Mountains to the northwest, the basins north of the Alaska Range to the north, the Canadian border to the east, and the Chugach Mountains to the south (Fig. 1). This region, hereafter called the study area, includes the Alaska Range, the Wrangell, Nutzotin, and Talkeetna mountains, the Copper River and the Susitna basins, the northern flank of the Chugach Mountains, the Aleutian Range, and the Alaska Peninsula. This chapter describes and interprets the bedrock geology of the region, which consists mostly of a collage of Paleozoic and Mesozoic...

@incollection{doi101130dnaggnag1311,
    author = "Nokleberg, Warren J. and Plafker, George and Wilson, Frederic H.",
    title = "Geology of south-central Alaska",
    year = "2015",
    booktitle = "Geological Society of America eBooks",
    abstract = "South-central Alaska is defined as the region bounded by the Kuskokwim Mountains to the northwest, the basins north of the Alaska Range to the north, the Canadian border to the east, and the Chugach Mountains to the south (Fig. 1). This region, hereafter called the study area, includes the Alaska Range, the Wrangell, Nutzotin, and Talkeetna mountains, the Copper River and the Susitna basins, the northern flank of the Chugach Mountains, the Aleutian Range, and the Alaska Peninsula. This chapter describes and interprets the bedrock geology of the region, which consists mostly of a collage of Paleozoic and Mesozoic...",
    url = "https://doi.org/10.1130/dnag-gna-g1.311",
    doi = "10.1130/dnag-gna-g1.311",
    openalex = "W119488528",
    references = "doi103133cir967"
}

You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.

@incollection{doi101130dnaggnag1813,
    author = "Hamilton, Thomas D.",
    title = "Late Cenozoic glaciation of Alaska",
    year = "2015",
    booktitle = "Geological Society of America eBooks",
    abstract = "You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.",
    url = "https://doi.org/10.1130/dnag-gna-g1.813",
    doi = "10.1130/dnag-gna-g1.813",
    openalex = "W2496479661",
    references = "doi101007978146133793516, doi103133cir967"
}

The Liscomb bonebed in the Price Creek Formation of northern Alaska has produced thousands of individual bones of a saurolophine hadrosaurid similar to Edmontosaurus; however, the specific identity of this taxon has been unclear, in part because the vast majority of the remains represent immature individuals. In this study, we address the taxonomic status of the Alaskan material through a comparative and quantitative morphological analysis of juvenile as well several near adult-sized specimens with particular reference to the two known species of Edmontosaurus, as well as a cladistic analysis using two different matrices for Hadrosauroidea. In the comparative morphological analysis, we introduce a quantitative method using bivariate plots to address ontogenetic variation. Our comparative anatomical analysis reveals that the Alaskan saurolophine possesses a unique suite of characters that distinguishes it from Edmontosaurus, including a premaxillary circumnarial ridge that projects posterolaterally without a premaxillary vestibular promontory, a shallow groove lateral to the posterodorsal premaxillary foramen, a relatively narrow jugal process of the postorbital lacking a postorbital pocket, a relatively tall maxilla, a relatively gracile jugal, a more strongly angled posterior margin of the anterior process of the jugal, wide lateral exposure of the quadratojugal, and a short symphyseal process of the dentary. The cladistic analyses consistently recover the Alaskan saurolophine as the sister taxon to Edmontosaurus annectens + Edmontosaurus regalis. This phylogenetic assessment is robust even when accounting for ontogenetically variable characters. Based on these results, we erect a new taxon, Ugrunaaluk kuukpikensis gen. et sp. nov. that contributes to growing evidence for a distinct, early Maastrichtian Arctic dinosaur community that existed at the northernmost extent of Laramidia during the Late Cretaceous.

@article{doi104202app001522015,
    author = "Mori, Hirotsugu and Druckenmiller, Patrick S. and Erickson, Gregory M.",
    title = "A new Arctic hadrosaurid (Dinosauria: Hadrosauridae) from the Prince Creek Formation (lower Maastrichtian) of northern Alaska",
    year = "2015",
    journal = "Acta Palaeontologica Polonica",
    abstract = "The Liscomb bonebed in the Price Creek Formation of northern Alaska has produced thousands of individual bones of a saurolophine hadrosaurid similar to Edmontosaurus; however, the specific identity of this taxon has been unclear, in part because the vast majority of the remains represent immature individuals. In this study, we address the taxonomic status of the Alaskan material through a comparative and quantitative morphological analysis of juvenile as well several near adult-sized specimens with particular reference to the two known species of Edmontosaurus, as well as a cladistic analysis using two different matrices for Hadrosauroidea. In the comparative morphological analysis, we introduce a quantitative method using bivariate plots to address ontogenetic variation. Our comparative anatomical analysis reveals that the Alaskan saurolophine possesses a unique suite of characters that distinguishes it from Edmontosaurus, including a premaxillary circumnarial ridge that projects posterolaterally without a premaxillary vestibular promontory, a shallow groove lateral to the posterodorsal premaxillary foramen, a relatively narrow jugal process of the postorbital lacking a postorbital pocket, a relatively tall maxilla, a relatively gracile jugal, a more strongly angled posterior margin of the anterior process of the jugal, wide lateral exposure of the quadratojugal, and a short symphyseal process of the dentary. The cladistic analyses consistently recover the Alaskan saurolophine as the sister taxon to Edmontosaurus annectens + Edmontosaurus regalis. This phylogenetic assessment is robust even when accounting for ontogenetically variable characters. Based on these results, we erect a new taxon, Ugrunaaluk kuukpikensis gen. et sp. nov. that contributes to growing evidence for a distinct, early Maastrichtian Arctic dinosaur community that existed at the northernmost extent of Laramidia during the Late Cretaceous.",
    url = "https://doi.org/10.4202/app.00152.2015",
    doi = "10.4202/app.00152.2015",
    openalex = "W2286407842",
    references = "davies1987duckbill, doi101002ajpa21090, doi101017s1464793106007007, doi10102990jb01916, doi10108014786440109462720, doi101111j10960031200800217x, doi101139e11017, doi1023071005355, doi102475ajss319111253, doi104202app20110033, openalexw2183707334, openalexw2611511275, openalexw634659594"
}

@article{doi101016jpalaeo201507024,
    author = "Fiorillo, A. and McCarthy, P. and Flaig, P.",
    title = "A multi-disciplinary perspective on habitat preferences among dinosaurs in a Cretaceous Arctic greenhouse world, North Slope, Alaska (Prince Creek Formation: Lower Maastrichtian)",
    year = "2016",
    journal = "Palaeogeography, Palaeoclimatology, Palaeoecology",
    url = "https://www.semanticscholar.org/paper/b109046bdbe3b56ff77617cf8875f1dc74a2dc77",
    doi = "10.1016/J.PALAEO.2015.07.024",
    is_oa = "true",
    pages = "377-389",
    semanticscholar_citation_count = "18",
    semanticscholar_id = "b109046bdbe3b56ff77617cf8875f1dc74a2dc77",
    volume = "441"
}

The sauropod dinosaur Alamosaurus sanjuanensis Gilmore, 1922 has been known from Maastrichtian deposits of south-western North America for nearly a century. Alamosaurus is the youngest sauropod taxon known in North America. Originally described from an isolated scapula and ischium from New Mexico, more of Alamosaurus was revealed by an incomplete skeleton from southern Utah. Additional referred specimens from western Texas provided the first few examples of cervical, dorsal and sacral vertebrae known for the taxon, but these came from relatively small and immature individuals. Here we describe an articulated series of cervical vertebrae of a large, mature titanosaur from Big Bend National Park, Texas, and provide evidence that the specimen can be referred to A. sanjuanensis. The specimen represents the first articulated cervical vertebral series described for the taxon, which clarifies aspects of cervical vertebral anatomy and provides at least one new diagnostic character for Alamosaurus. Many previous cladistic analyses found Alamosaurus to be a saltasaurid titanosaur, sometimes closely related to the Asian taxon Opisthocoelicaudia skarzynskii. We present cladistic analyses incorporating new data from this and other specimens from Big Bend National Park. The first places Alamosaurus as a lithostrotian titanosaur outside Saltasauridae. The second analysis, with greater focus on South American titanosaurs, finds Alamosaurus allied to Lognkosauria, a clade of South American titanosaurs notable for giant size and exceptionally robust necks. This relationship may be more congruent with the fossil record than hypotheses of phylogeny that would require saltasaurid titanosaurs to inhabit northern Laramidia, Beringia and Central Asia through the late Campanian and Maastrichtian while leaving no record of their presence.

@article{doi1010801477201920161183150,
    author = "Tykoski, Ronald S. and Fiorillo, Anthony R.",
    title = "An articulated cervical series of Alamosaurus sanjuanensis Gilmore, 1922 (Dinosauria, Sauropoda) from Texas: new perspective on the relationships of North America's last giant sauropod",
    year = "2016",
    journal = "Journal of Systematic Palaeontology",
    abstract = "The sauropod dinosaur Alamosaurus sanjuanensis Gilmore, 1922 has been known from Maastrichtian deposits of south-western North America for nearly a century. Alamosaurus is the youngest sauropod taxon known in North America. Originally described from an isolated scapula and ischium from New Mexico, more of Alamosaurus was revealed by an incomplete skeleton from southern Utah. Additional referred specimens from western Texas provided the first few examples of cervical, dorsal and sacral vertebrae known for the taxon, but these came from relatively small and immature individuals. Here we describe an articulated series of cervical vertebrae of a large, mature titanosaur from Big Bend National Park, Texas, and provide evidence that the specimen can be referred to A. sanjuanensis. The specimen represents the first articulated cervical vertebral series described for the taxon, which clarifies aspects of cervical vertebral anatomy and provides at least one new diagnostic character for Alamosaurus. Many previous cladistic analyses found Alamosaurus to be a saltasaurid titanosaur, sometimes closely related to the Asian taxon Opisthocoelicaudia skarzynskii. We present cladistic analyses incorporating new data from this and other specimens from Big Bend National Park. The first places Alamosaurus as a lithostrotian titanosaur outside Saltasauridae. The second analysis, with greater focus on South American titanosaurs, finds Alamosaurus allied to Lognkosauria, a clade of South American titanosaurs notable for giant size and exceptionally robust necks. This relationship may be more congruent with the fossil record than hypotheses of phylogeny that would require saltasaurid titanosaurs to inhabit northern Laramidia, Beringia and Central Asia through the late Campanian and Maastrichtian while leaving no record of their presence.",
    url = "https://doi.org/10.1080/14772019.2016.1183150",
    doi = "10.1080/14772019.2016.1183150",
    openalex = "W4239226469",
    references = "doi101016jjsames201411008, doi101016jpalaeo200901002, doi101080027246342012671204, doi1011646zootaxa384811, doi104202app20110033, doi105710amegh261210131889, fiorillo2014herd"
}

@misc{helsel2016north,
    author = "Helsel, Frederick and Dexheimer, Darielle and Lucero, Daniel",
    title = "North Slope of Alaska ARM Facilities.",
    year = "2016",
    url = "https://doi.org/10.2172/1431186",
    doi = "10.2172/1431186"
}

For the first time a dinosaur track site is identified in Maastrichtian paleopolar coastal plain deposits of the Prince Creek Formation (PCF) along the Colville River, North Slope of Alaska. Tracks were made and preserved by trampling of an ash-covered swamp margin, subsequent filling of tracks with alluvium from nearby rivers, and modification of sediments by pedogensis. Tracks are grouped into three classes based on track width and depth, with the largest tracks (>800 mm wide) recording overstepping by multiple individuals. As no bedding plane views of the tracks are present, the true shapes of the tracks were not available and, thus, a high probability of identification is not achievable. The tracks can be interpreted, however, using hypothetical-deductive reasoning by integrating paleontological and ichnological data from local and regional outcrops. The tracks likely represent the presence of hadrosaurs based on the overwhelming percentage of hadrosaur fossils that comprise nearby bonebeds, dominated by juvenile hadrosaurs (∼ 99%); to date no adult hadrosaur bone has been documented in the PCF. This interpretation is also supported by comparison of PCF hadrosaur track dimensions to exquisitely preserved (three-dimensional tracks with skin impressions) trackways of the coeval Cantwell Formation in Denali National Park (DENA), central Alaska. PCF track size dimensions, in comparison to DENA tracks, also represent a series of growth stages including both juvenile and adult hadrosaurs, and indicate that multiple generations and sizes of individuals lived and traveled together on the Arctic Alaska coastal plain. This is the first evidence for adult hadrosaurs in the PCF. This track site also preserves the highest latitude Maastrichtian footprints known.

@article{doi1010801042094020171337011,
    author = "Flaig, Peter P. and Hasiotis, Stephen T. and Fiorillo, Anthony R.",
    title = "A Paleopolar Dinosaur Track Site in the Cretaceous (Maastrichtian) Prince Creek Formation of Arctic Alaska: Track Characteristics and Probable Trackmakers",
    year = "2017",
    journal = "Ichnos/Ichnos : an international journal for plant and animal traces",
    abstract = "For the first time a dinosaur track site is identified in Maastrichtian paleopolar coastal plain deposits of the Prince Creek Formation (PCF) along the Colville River, North Slope of Alaska. Tracks were made and preserved by trampling of an ash-covered swamp margin, subsequent filling of tracks with alluvium from nearby rivers, and modification of sediments by pedogensis. Tracks are grouped into three classes based on track width and depth, with the largest tracks (>800 mm wide) recording overstepping by multiple individuals. As no bedding plane views of the tracks are present, the true shapes of the tracks were not available and, thus, a high probability of identification is not achievable. The tracks can be interpreted, however, using hypothetical-deductive reasoning by integrating paleontological and ichnological data from local and regional outcrops. The tracks likely represent the presence of hadrosaurs based on the overwhelming percentage of hadrosaur fossils that comprise nearby bonebeds, dominated by juvenile hadrosaurs (∼ 99\%); to date no adult hadrosaur bone has been documented in the PCF. This interpretation is also supported by comparison of PCF hadrosaur track dimensions to exquisitely preserved (three-dimensional tracks with skin impressions) trackways of the coeval Cantwell Formation in Denali National Park (DENA), central Alaska. PCF track size dimensions, in comparison to DENA tracks, also represent a series of growth stages including both juvenile and adult hadrosaurs, and indicate that multiple generations and sizes of individuals lived and traveled together on the Arctic Alaska coastal plain. This is the first evidence for adult hadrosaurs in the PCF. This track site also preserves the highest latitude Maastrichtian footprints known.",
    url = "https://doi.org/10.1080/10420940.2017.1337011",
    doi = "10.1080/10420940.2017.1337011",
    openalex = "W2736106342",
    references = "doi101016jpalaeo201002029, doi101016s0031018202006892, doi101080147720192010509356, doi102110palo2009p09103r, doi104202app001522015, doi104202app20110033, fiorillo2014herd"
}

@incollection{bart20194,
    author = "Bart, Jonathan and Brown, Stephen and Andres, Brad A. and Platte, Robert and Manning, Ann",
    title = "4. NORTH SLOPE OF ALASKA",
    year = "2019",
    booktitle = "Arctic Shorebirds in North America",
    url = "https://doi.org/10.1525/9780520953499-006",
    doi = "10.1525/9780520953499-006",
    pages = "37-96"
}

In the lead-up to the Cretaceous/Paleogene mass extinction, dinosaur diversity is argued to have been either in long-term decline, or thriving until their sudden demise. The latest Cretaceous (Campanian-Maastrichtian [83-66 Ma]) of North America provides the best record to address this debate, but even here diversity reconstructions are biased by uneven sampling. Here we combine fossil occurrences with climatic and environmental modelling to quantify latest Cretaceous North American dinosaur habitat. Ecological niche modelling shows a Campanian-to-Maastrichtian habitability decrease in areas with present-day rock-outcrop. However, a continent-wide projection demonstrates habitat stability, or even a Campanian-to-Maastrichtian increase, that is not preserved. This reduction of the spatial sampling window resulted from formation of the proto-Rocky Mountains and sea-level regression. We suggest that Maastrichtian North American dinosaur diversity is therefore likely to be underestimated, with the apparent decline a product of sampling bias, and not due to a climatically-driven decrease in habitability as previously hypothesised.

@article{doi101038s41467019089972,
    author = "Chiarenza, Alfio Alessandro and Mannion, Philip D. and Lunt, Daniel J. and Farnsworth, Alex and Jones, Lewis A. and Kelland, Sarah-Jane and Allison, Peter A.",
    title = "Ecological niche modelling does not support climatically-driven dinosaur diversity decline before the Cretaceous/Paleogene mass extinction",
    year = "2019",
    journal = "Nature Communications",
    abstract = "In the lead-up to the Cretaceous/Paleogene mass extinction, dinosaur diversity is argued to have been either in long-term decline, or thriving until their sudden demise. The latest Cretaceous (Campanian-Maastrichtian [83-66 Ma]) of North America provides the best record to address this debate, but even here diversity reconstructions are biased by uneven sampling. Here we combine fossil occurrences with climatic and environmental modelling to quantify latest Cretaceous North American dinosaur habitat. Ecological niche modelling shows a Campanian-to-Maastrichtian habitability decrease in areas with present-day rock-outcrop. However, a continent-wide projection demonstrates habitat stability, or even a Campanian-to-Maastrichtian increase, that is not preserved. This reduction of the spatial sampling window resulted from formation of the proto-Rocky Mountains and sea-level regression. We suggest that Maastrichtian North American dinosaur diversity is therefore likely to be underestimated, with the apparent decline a product of sampling bias, and not due to a climatically-driven decrease in habitability as previously hypothesised.",
    url = "https://doi.org/10.1038/s41467-019-08997-2",
    doi = "10.1038/s41467-019-08997-2",
    openalex = "W2919866498",
    references = "doi101016jecolmodel201312012, doi101016jpalaeo201602033, doi101038nature15697, doi101038ncomms1815, doi101073pnas0901637106, doi101073pnas1521478113, doi10108008912969009386535, doi101111ecog03049, doi101111j13652664200601214x, doi101111j14724642201000725x, doi101111pala12329, doi101126science3287615, doi1012019781315140919, doi101371journalpone0079420, doi1018900721531, doi1023071931034, doi103897zookeys4698439, lehman1987late"
}

The Prince Creek Formation of Alaska, a rock unit that represents lower coastal plain and delta deposits, is one of the most important formations in the world for understanding vertebrate ecology in the Arctic during the Cretaceous. Here we report on an isolated cranial material, supraoccipital, of a lambeosaurine hadrosaurid from the Liscomb Bonebed of the Prince Creek Formation. The lambeosaurine supraoccipital has well-developed squamosal bosses and a short sutural surface with the exoccipital-opisthotic complex, and is similar to lambeosaurine supraoccipitals from the Dinosaur Park Formation in having anteriorly positioned squamosal bosses. Affinities with Canadian lambeosaurines elucidate more extensive faunal exchange between the Arctic and lower paleolatitudes which was previously suggested by the presence of Edmontosaurus, Pachyrhinosaurus, tyrannosaurids, and troodontids in both regions. The presence of one lambeosaurine and nine hadrosaurine supraoccipitals in the Liscomb Bonebed suggests hadrosaurine dominated faunal structure as in the Careless Creek Quarry of the USA that was also deposited under a near-shore environment. It differs from the lambeosaurine dominant structures of localities in Russia and China interpreted as inland environments. This may suggest that lambeosaurines had less preference for near-shore environments than hadrosaurines in both Arctic and lower paleolatitudes.

@article{doi101038s41598019413258,
    author = "Takasaki, Ryuji and Fiorillo, Anthony R. and Kobayashi, Yoshitsugu and Tykoski, Ronald S. and McCarthy, Paul J.",
    title = "The First Definite Lambeosaurine Bone From the Liscomb Bonebed of the Upper Cretaceous Prince Creek Formation, Alaska, United States",
    year = "2019",
    journal = "Scientific Reports",
    abstract = "The Prince Creek Formation of Alaska, a rock unit that represents lower coastal plain and delta deposits, is one of the most important formations in the world for understanding vertebrate ecology in the Arctic during the Cretaceous. Here we report on an isolated cranial material, supraoccipital, of a lambeosaurine hadrosaurid from the Liscomb Bonebed of the Prince Creek Formation. The lambeosaurine supraoccipital has well-developed squamosal bosses and a short sutural surface with the exoccipital-opisthotic complex, and is similar to lambeosaurine supraoccipitals from the Dinosaur Park Formation in having anteriorly positioned squamosal bosses. Affinities with Canadian lambeosaurines elucidate more extensive faunal exchange between the Arctic and lower paleolatitudes which was previously suggested by the presence of Edmontosaurus, Pachyrhinosaurus, tyrannosaurids, and troodontids in both regions. The presence of one lambeosaurine and nine hadrosaurine supraoccipitals in the Liscomb Bonebed suggests hadrosaurine dominated faunal structure as in the Careless Creek Quarry of the USA that was also deposited under a near-shore environment. It differs from the lambeosaurine dominant structures of localities in Russia and China interpreted as inland environments. This may suggest that lambeosaurines had less preference for near-shore environments than hadrosaurines in both Arctic and lower paleolatitudes.",
    url = "https://doi.org/10.1038/s41598-019-41325-8",
    doi = "10.1038/s41598-019-41325-8",
    openalex = "W2925079322",
    references = "doi104202app001522015"
}

The non-marine Horseshoe Canyon Formation (HCFm, southern Alberta) yields taxonomically diverse, late Campanian to middle Maastrichtian dinosaur assemblages that play a central role in documenting dinosaur evolution, paleoecology, and paleobiogeography leading up to the end-Cretaceous extinction. Here, we present high-precision U–Pb CA–ID–TIMS ages and the first calibrated chronostratigraphy for the HCFm using zircon grains from (1) four HCFm bentonites distributed through 129 m of section, (2) one bentonite from the underlying Bearpaw Formation, and (3) a bentonite from the overlying Battle Formation that we dated previously. In its type area, the HCFm ranges in age from 73.1–68.0 Ma. Significant paleoenvironmental and climatic changes are recorded in the formation, including (1) a transition from a warm-and-wet deltaic setting to a cooler, seasonally wet-dry coastal plain at 71.5 Ma, (2) maximum transgression of the Drumheller Marine Tongue at 70.896 ± 0.048 Ma, and (3) transition to a warm-wet alluvial plain at 69.6 Ma. The HCFm’s three mega-herbivore dinosaur assemblage zones track these changes and are calibrated as follows: Edmontosaurus regalis – Pachyrhinosaurus canadensis zone, 73.1–71.5 Ma; Hypacrosaurus altispinus – Saurolophus osborni zone, 71.5–69.6 Ma; and Eotriceratops xerinsularis zone, 69.6–68.2 Ma. The Albertosaurus Bonebed — a monodominant assemblage of tyrannosaurids in the Tolman Member — is assessed an age of 70.1 Ma. The unusual triceratopsin, Eotriceratops xerinsularis, from the Carbon Member, is assessed an age of 68.8 Ma. This chronostratigraphy is useful for refining correlations with dinosaur-bearing upper Campanian–middle Maastrichtian units in Alberta and elsewhere in North America.

@article{doi101139cjes20190019,
    author = "Eberth, David A. and Kamo, Sandra L.",
    title = "High-precision U–Pb CA–ID–TIMS dating and chronostratigraphy of the dinosaur-rich Horseshoe Canyon Formation (Upper Cretaceous, Campanian–Maastrichtian), Red Deer River valley, Alberta, Canada",
    year = "2019",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "The non-marine Horseshoe Canyon Formation (HCFm, southern Alberta) yields taxonomically diverse, late Campanian to middle Maastrichtian dinosaur assemblages that play a central role in documenting dinosaur evolution, paleoecology, and paleobiogeography leading up to the end-Cretaceous extinction. Here, we present high-precision U–Pb CA–ID–TIMS ages and the first calibrated chronostratigraphy for the HCFm using zircon grains from (1) four HCFm bentonites distributed through 129 m of section, (2) one bentonite from the underlying Bearpaw Formation, and (3) a bentonite from the overlying Battle Formation that we dated previously. In its type area, the HCFm ranges in age from 73.1–68.0 Ma. Significant paleoenvironmental and climatic changes are recorded in the formation, including (1) a transition from a warm-and-wet deltaic setting to a cooler, seasonally wet-dry coastal plain at 71.5 Ma, (2) maximum transgression of the Drumheller Marine Tongue at 70.896 ± 0.048 Ma, and (3) transition to a warm-wet alluvial plain at 69.6 Ma. The HCFm’s three mega-herbivore dinosaur assemblage zones track these changes and are calibrated as follows: Edmontosaurus regalis – Pachyrhinosaurus canadensis zone, 73.1–71.5 Ma; Hypacrosaurus altispinus – Saurolophus osborni zone, 71.5–69.6 Ma; and Eotriceratops xerinsularis zone, 69.6–68.2 Ma. The Albertosaurus Bonebed — a monodominant assemblage of tyrannosaurids in the Tolman Member — is assessed an age of 70.1 Ma. The unusual triceratopsin, Eotriceratops xerinsularis, from the Carbon Member, is assessed an age of 68.8 Ma. This chronostratigraphy is useful for refining correlations with dinosaur-bearing upper Campanian–middle Maastrichtian units in Alberta and elsewhere in North America.",
    url = "https://doi.org/10.1139/cjes-2019-0019",
    doi = "10.1139/cjes-2019-0019",
    openalex = "W2979872101",
    references = "andeberth2016new, doi101007springerreference4923, doi1010160016703773902135, doi101016jchemgeo200503011, doi101016jgca200509007, doi101016jgca201006017, doi101016s0009254196000332, doi101016s0195667105800308, doi101073pnas1313334111, doi101103physrevc41889, doi101126science1154339, doi101126science1230492, doi101139cjes20120185, doi101371journalpone0188426, doi104202app20110033, doi105860choice435902, openalexw2989049194"
}

@article{doi101016jmarpetgeo2020104748,
    author = "Yoneda, Jun and Jin, Yusuke and Muraoka, Michihiro and Oshima, Motoi and Suzuki, Kiyofumi and Walker, Mike and Otsuki, Satoshi and Kumagai, Kenichi and Collett, Timothy S. and Boswell, Ray and Okinaka, Norihiro",
    title = "Multiple physical properties of gas hydrate-bearing sediments recovered from Alaska North Slope 2018 Hydrate-01 Stratigraphic Test Well",
    year = "2020",
    journal = "Marine and Petroleum Geology",
    url = "https://doi.org/10.1016/j.marpetgeo.2020.104748",
    doi = "10.1016/j.marpetgeo.2020.104748",
    openalex = "W3094090064",
    references = "doi101016jmarpetgeo200910001"
}

The unexpected discovery of non-avian dinosaurs from Arctic and Antarctic settings has generated considerable debate about whether they had the capacity to reproduce at high latitudes-especially the larger-bodied, hypothetically migratory taxa. Evidence for dinosaurian polar reproduction remains very rare, particularly for species that lived at the highest paleolatitudes (>75°). Here we report the discovery of perinatal and very young dinosaurs from the highest known paleolatitude for the clade-the Cretaceous Prince Creek Formation (PCF) of northern Alaska. These data demonstrate Arctic reproduction in a diverse assemblage of large- and small-bodied ornithischian and theropod species. In terms of overall diversity, 70% of the known dinosaurian families, as well as avialans (birds), in the PCF are represented by perinatal individuals, the highest percentage for any North American Cretaceous formation. These findings, coupled with prolonged incubation periods, small neonate sizes, and short reproductive windows suggest most, if not all, PCF dinosaurs were nonmigratory year-round Arctic residents. Notably, we reconstruct an annual chronology of reproductive events for the ornithischian dinosaurs using refined paleoenvironmental/plant phenology data and new insights into dinosaur incubation periods. Seasonal resource limitations due to extended periods of winter darkness and freezing temperatures placed severe constraints on dinosaurian reproduction, development, and maintenance, suggesting these taxa showed polar-specific life history strategies, including endothermy.

@article{doi101016jcub202105041,
    author = "Druckenmiller, Patrick S and Erickson, Gregory M and Brinkman, Donald and Brown, Caleb M and Eberle, Jaelyn J",
    title = "Nesting at extreme polar latitudes by non-avian dinosaurs.",
    year = "2021",
    journal = "Current biology: CB",
    abstract = "The unexpected discovery of non-avian dinosaurs from Arctic and Antarctic settings has generated considerable debate about whether they had the capacity to reproduce at high latitudes-especially the larger-bodied, hypothetically migratory taxa. Evidence for dinosaurian polar reproduction remains very rare, particularly for species that lived at the highest paleolatitudes (>75°). Here we report the discovery of perinatal and very young dinosaurs from the highest known paleolatitude for the clade-the Cretaceous Prince Creek Formation (PCF) of northern Alaska. These data demonstrate Arctic reproduction in a diverse assemblage of large- and small-bodied ornithischian and theropod species. In terms of overall diversity, 70\% of the known dinosaurian families, as well as avialans (birds), in the PCF are represented by perinatal individuals, the highest percentage for any North American Cretaceous formation. These findings, coupled with prolonged incubation periods, small neonate sizes, and short reproductive windows suggest most, if not all, PCF dinosaurs were nonmigratory year-round Arctic residents. Notably, we reconstruct an annual chronology of reproductive events for the ornithischian dinosaurs using refined paleoenvironmental/plant phenology data and new insights into dinosaur incubation periods. Seasonal resource limitations due to extended periods of winter darkness and freezing temperatures placed severe constraints on dinosaurian reproduction, development, and maintenance, suggesting these taxa showed polar-specific life history strategies, including endothermy.",
    url = "https://pubmed.ncbi.nlm.nih.gov/34171301/",
    doi = "10.1016/j.cub.2021.05.041",
    openalex = "W3174184361",
    pmid = "34171301",
    references = "doi101017s1477201907002271, doi101029sc005p0175, doi101038385247a0, doi101038nature01342, doi101038nature02699, doi101038nature02855, doi10113008137233291, doi101130spe332, doi101139cjes20200169, doi1012703p639, doi1016710272463420000200115lbhoth20co2, doi104202app001522015"
}

The spectacular fossil fauna and flora preserved in the Upper Cretaceous terrestrial strata of North America's Western Interior Basin record an exceptional peak in the diversification of fossil vertebrates in the Campanian, which has been termed the 'zenith of dinosaur diversity'. The wide latitudinal distribution of rocks and fossils that represent this episode, spanning from northern Mexico to the northern slopes of Alaska, provides a unique opportunity to gain insights into dinosaur paleoecology and to address outstanding questions regarding faunal provinciality in connection to paleogeography and climate. Whereas reliable basin-wide correlations are fundamental to investigations of this sort, three decades of radioisotope geochronology of various vintages and limited compatibility has complicated correlation of distant fossil-bearing successions and given rise to contradictory paleobiogeographic and evolutionary hypotheses. Here we present new U-Pb geochronology by the CA-ID-TIMS method for 16 stratigraphically well constrained bentonite beds, ranging in age from 82.419 ± 0.074 Ma to 73.496 ± 0.039 Ma (2σ internal uncertainties), and the resulting Bayesian age models for six key fossil-bearing formations over a 1600 km latitudinal distance from northwest New Mexico, USA to southern Alberta, Canada. Our high-resolution chronostratigraphic framework for the upper Campanian of the Western Interior Basin reveals that despite their contrasting depositional settings and basin evolution histories, significant age overlap exists between the main fossil-bearing intervals of the Kaiparowits Formation (southern Utah), Judith River Formation (central Montana), Two Medicine Formation (western Montana) and Dinosaur Park Formation (southern Alberta). Pending more extensive paleontologic collecting that would allow more rigorous faunal analyses, our results support a first-order connection between paleoecologic and fossil diversities and help overcome the chronostratigraphic ambiguities that have impeded the testing of proposed models of latitudinal provinciality of dinosaur taxa during the Campanian.

@article{doi101038s4159802219896w,
    author = "Ramezani, Jahandar and Beveridge, Tegan L and Rogers, Raymond R and Eberth, David A and Roberts, Eric M",
    title = "Calibrating the zenith of dinosaur diversity in the Campanian of the Western Interior Basin by CA-ID-TIMS U-Pb geochronology.",
    year = "2022",
    journal = "Scientific reports",
    abstract = "The spectacular fossil fauna and flora preserved in the Upper Cretaceous terrestrial strata of North America's Western Interior Basin record an exceptional peak in the diversification of fossil vertebrates in the Campanian, which has been termed the 'zenith of dinosaur diversity'. The wide latitudinal distribution of rocks and fossils that represent this episode, spanning from northern Mexico to the northern slopes of Alaska, provides a unique opportunity to gain insights into dinosaur paleoecology and to address outstanding questions regarding faunal provinciality in connection to paleogeography and climate. Whereas reliable basin-wide correlations are fundamental to investigations of this sort, three decades of radioisotope geochronology of various vintages and limited compatibility has complicated correlation of distant fossil-bearing successions and given rise to contradictory paleobiogeographic and evolutionary hypotheses. Here we present new U-Pb geochronology by the CA-ID-TIMS method for 16 stratigraphically well constrained bentonite beds, ranging in age from 82.419 ± 0.074 Ma to 73.496 ± 0.039 Ma (2σ internal uncertainties), and the resulting Bayesian age models for six key fossil-bearing formations over a 1600 km latitudinal distance from northwest New Mexico, USA to southern Alberta, Canada. Our high-resolution chronostratigraphic framework for the upper Campanian of the Western Interior Basin reveals that despite their contrasting depositional settings and basin evolution histories, significant age overlap exists between the main fossil-bearing intervals of the Kaiparowits Formation (southern Utah), Judith River Formation (central Montana), Two Medicine Formation (western Montana) and Dinosaur Park Formation (southern Alberta). Pending more extensive paleontologic collecting that would allow more rigorous faunal analyses, our results support a first-order connection between paleoecologic and fossil diversities and help overcome the chronostratigraphic ambiguities that have impeded the testing of proposed models of latitudinal provinciality of dinosaur taxa during the Campanian.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC9512893/",
    doi = "10.1038/s41598-022-19896-w",
    pmcid = "PMC9512893",
    pmid = "36163377"
}

The partially correlative Alaskan dinosaur-bearing Prince Creek Formation (PCF), North Slope, lower Cantwell Formation (LCF), Denali National Park, and Chignik Formation (CF), Aniakchak National Monument, form an N–S transect that, together, provides an unparalleled opportunity to examine an ancient high-latitude terrestrial ecosystem. The PCF, 75–85° N paleolatitude, had a Mean Annual Temperature (MAT) of ~5–7 °C and a Mean Annual Precipitation (MAP) of ~1250 mm/year. The LCF, ~71° N paleolatitude, had a MAT of ~7.4 °C and MAP of ~661 mm/year. The CF, ~57° N paleolatitude, had a MAT of ~13 °C and MAP of ~1090 mm/year. The relative abundances of the large-bodied herbivorous dinosaurs, hadrosaurids and ceratopsids, vary along this transect, suggesting that these climatic differences (temperature and precipitation) played a role in the ecology of these large-bodied herbivores of the ancient north. MAP played a more direct role in their distribution than MAT, and the seasonal temperature range may have played a secondary role.

@article{doi103390geosciences12040161,
    author = "Fiorillo, A. and McCarthy, P. and Kobayashi, Y. and Suarez, M.",
    title = "Cretaceous Dinosaurs across Alaska Show the Role of Paleoclimate in Structuring Ancient Large-Herbivore Populations",
    year = "2022",
    journal = "Geosciences",
    abstract = "The partially correlative Alaskan dinosaur-bearing Prince Creek Formation (PCF), North Slope, lower Cantwell Formation (LCF), Denali National Park, and Chignik Formation (CF), Aniakchak National Monument, form an N–S transect that, together, provides an unparalleled opportunity to examine an ancient high-latitude terrestrial ecosystem. The PCF, 75–85° N paleolatitude, had a Mean Annual Temperature (MAT) of \textasciitilde 5–7 °C and a Mean Annual Precipitation (MAP) of \textasciitilde 1250 mm/year. The LCF, \textasciitilde 71° N paleolatitude, had a MAT of \textasciitilde 7.4 °C and MAP of \textasciitilde 661 mm/year. The CF, \textasciitilde 57° N paleolatitude, had a MAT of \textasciitilde 13 °C and MAP of \textasciitilde 1090 mm/year. The relative abundances of the large-bodied herbivorous dinosaurs, hadrosaurids and ceratopsids, vary along this transect, suggesting that these climatic differences (temperature and precipitation) played a role in the ecology of these large-bodied herbivores of the ancient north. MAP played a more direct role in their distribution than MAT, and the seasonal temperature range may have played a secondary role.",
    url = "https://www.mdpi.com/2076-3263/12/4/161/pdf?version=1648900160",
    doi = "10.3390/geosciences12040161",
    is_oa = "true",
    number = "4",
    pages = "161",
    semanticscholar_citation_count = "4",
    semanticscholar_id = "9222e1b51966f4ba5c2a9b864eec3e4bda762f58",
    volume = "12"
}

Abstract Baseline information about declining North American shorebird populations is essential to determine the effects of global warming at low-lying coastal areas of the Arctic and subarctic, where numerous taxa breed, and to assess population recovery throughout their range. We estimated population sizes on the Yukon–Kuskokwim Delta (YKD) in western Alaska on the eastern edge of the Bering Sea. We conducted ground-based surveys during 2015 and 2016 at 589 randomly selected plots from an area of 35,769 km2. We used stratified random sampling in 8 physiographic strata and corrected population estimates using detection ratios derived from double sampling on a subset of plots. We detected 11,110 breeding individuals of 21 taxa. Western Sandpiper (Calidris mauri), Red-necked Phalarope (Phalaropus lobatus), Dunlin (subspecies C. alpina pacifica), and Wilson’s Snipe (Gallinago delicata) were the most abundant taxa. We estimated that ~7 million individual shorebirds were breeding on the entire YKD in 2015 and 2016. Our surveys of this region provided robust population estimates (coefficient of variations ≤ 0.35) for 14 species. Our results indicate that the YKD supports a large proportion of North America’s breeding populations of the Pacific Golden-Plover (Pluvialis fulva), the western population of a Whimbrel subspecies (Numenius phaeopus hudsonicus), a Bar-tailed Godwit subspecies (Limosa lapponica baueri), Black Turnstone (Arenaria melanocephala), a Dunlin subspecies (C. alpina pacifica), and Western Sandpiper. Our study highlights the importance of breeding shorebirds of this relatively pristine but climatically sensitive deltaic system. Estuaries and deltaic systems worldwide are rapidly being degraded by anthropogenic activities. Our population estimates can be used to refine prior North American population estimates, determine the effects of global warming, and evaluate conservation success by measuring population change over time.

@article{doi101093ornithappduad066,
    author = "Lyons, James E. and Brown, Stephen C. and Saalfeld, Sarah T. and Johnson, James A. and Andres, Brad A. and Sowl, Kristine M. and Gill, Robert E. and McCaffery, Brian J. and Kidd, Lindall R. and McGarvey, Metta and Winn, Brad and Gates, H. River and Granfors, Diane A. and Lanctot, Richard B.",
    title = "Alaska’s climate sensitive Yukon–Kuskokwim Delta supports seven million Arctic-breeding shorebirds, including the majority of six North American populations",
    year = "2023",
    journal = "Ornithological applications",
    abstract = "Abstract Baseline information about declining North American shorebird populations is essential to determine the effects of global warming at low-lying coastal areas of the Arctic and subarctic, where numerous taxa breed, and to assess population recovery throughout their range. We estimated population sizes on the Yukon–Kuskokwim Delta (YKD) in western Alaska on the eastern edge of the Bering Sea. We conducted ground-based surveys during 2015 and 2016 at 589 randomly selected plots from an area of 35,769 km2. We used stratified random sampling in 8 physiographic strata and corrected population estimates using detection ratios derived from double sampling on a subset of plots. We detected 11,110 breeding individuals of 21 taxa. Western Sandpiper (Calidris mauri), Red-necked Phalarope (Phalaropus lobatus), Dunlin (subspecies C. alpina pacifica), and Wilson’s Snipe (Gallinago delicata) were the most abundant taxa. We estimated that \textasciitilde 7 million individual shorebirds were breeding on the entire YKD in 2015 and 2016. Our surveys of this region provided robust population estimates (coefficient of variations ≤ 0.35) for 14 species. Our results indicate that the YKD supports a large proportion of North America’s breeding populations of the Pacific Golden-Plover (Pluvialis fulva), the western population of a Whimbrel subspecies (Numenius phaeopus hudsonicus), a Bar-tailed Godwit subspecies (Limosa lapponica baueri), Black Turnstone (Arenaria melanocephala), a Dunlin subspecies (C. alpina pacifica), and Western Sandpiper. Our study highlights the importance of breeding shorebirds of this relatively pristine but climatically sensitive deltaic system. Estuaries and deltaic systems worldwide are rapidly being degraded by anthropogenic activities. Our population estimates can be used to refine prior North American population estimates, determine the effects of global warming, and evaluate conservation success by measuring population change over time.",
    url = "https://doi.org/10.1093/ornithapp/duad066",
    doi = "10.1093/ornithapp/duad066",
    openalex = "W4390097986",
    references = "doi1014430arctic4239"
}

The Nanushuk Formation (Albian–Cenomanian) crops out over much of the central and western North Slope of Alaska, varying from ≈1500 to ≈250 m thick from west to northeast. The Nanushuk Formation records an inter-tonguing succession of marine and nonmarine conglomerate, sandstone, mudstone, and coal. These rock units comprise the Kukpowruk and Corwin formations of the former Nanushuk Group, respectively. Work presented here is centered in the foothills of the DeLong Mountains along the Kukpowruk River, from an area west of Igloo Mountain in the Coke Basin to the Barabara Syncline, approximately 80 km to the north. A radiometric date recovered from a tuff in our study area suggests a Cenomanian age for at least some of these rocks. Outcrops along the Kukpowruk River contain a well-preserved fossil flora previously recovered from marine, marginal marine, and terrestrial sediments. Our own work focuses on detailed measured sections of terrestrial rocks, interpretation of sedimentary facies and facies associations, and documentation of fossil vertebrates. Eight facies associations are identified in the study area that together are interpreted to represent meandering fluvial and upper delta plain environments. Plant fossils are common and include standing tree trunks up to 58 cm in diameter at some locations. Approximately 75 newly discovered tracksites, and a heretofore unknown, rich fossil vertebrate ichnofauna, are present. The ichnofaunal assemblage includes evidence of small and large theropod dinosaurs (including birds) and bipedal and quadrupedal ornithischian dinosaurs. Approximately 15% of the dinosaur ichnofauna record is represented by fossil bird tracks. Wood fragments from the Nanushuk Formation were analyzed for their carbon isotopic composition to relate δ13C to mean annual precipitation. Samples averaged −26.4‰ VPDB, suggesting an average MAP of 1412 mm/year. This record of increased precipitation in the Nanushuk Fm. during the mid-Cretaceous provides new data that supports global precipitation patterns associated with the Cretaceous Thermal Maximum. This work provides an important framework for much-needed further paleoecological and paleoclimatic analyses into greenhouse conditions in the terrestrial Cretaceous Arctic during this important window in time.

@article{doi103390geosciences14020036,
    author = "Fiorillo, A. and McCarthy, P. and Shimer, G. and Suarez, Marina B. and Takasaki, R. and Chinzorig, Tsogtbaatar and Kobayashi, Y. and O’Sullivan, P. and Orphys, Eric",
    title = "New Dinosaur Ichnological, Sedimentological, and Geochemical Data from a Cretaceous High-Latitude Terrestrial Greenhouse Ecosystem, Nanushuk Formation, North Slope, Alaska",
    year = "2024",
    journal = "Geosciences",
    abstract = "The Nanushuk Formation (Albian–Cenomanian) crops out over much of the central and western North Slope of Alaska, varying from ≈1500 to ≈250 m thick from west to northeast. The Nanushuk Formation records an inter-tonguing succession of marine and nonmarine conglomerate, sandstone, mudstone, and coal. These rock units comprise the Kukpowruk and Corwin formations of the former Nanushuk Group, respectively. Work presented here is centered in the foothills of the DeLong Mountains along the Kukpowruk River, from an area west of Igloo Mountain in the Coke Basin to the Barabara Syncline, approximately 80 km to the north. A radiometric date recovered from a tuff in our study area suggests a Cenomanian age for at least some of these rocks. Outcrops along the Kukpowruk River contain a well-preserved fossil flora previously recovered from marine, marginal marine, and terrestrial sediments. Our own work focuses on detailed measured sections of terrestrial rocks, interpretation of sedimentary facies and facies associations, and documentation of fossil vertebrates. Eight facies associations are identified in the study area that together are interpreted to represent meandering fluvial and upper delta plain environments. Plant fossils are common and include standing tree trunks up to 58 cm in diameter at some locations. Approximately 75 newly discovered tracksites, and a heretofore unknown, rich fossil vertebrate ichnofauna, are present. The ichnofaunal assemblage includes evidence of small and large theropod dinosaurs (including birds) and bipedal and quadrupedal ornithischian dinosaurs. Approximately 15\% of the dinosaur ichnofauna record is represented by fossil bird tracks. Wood fragments from the Nanushuk Formation were analyzed for their carbon isotopic composition to relate δ13C to mean annual precipitation. Samples averaged −26.4‰ VPDB, suggesting an average MAP of 1412 mm/year. This record of increased precipitation in the Nanushuk Fm. during the mid-Cretaceous provides new data that supports global precipitation patterns associated with the Cretaceous Thermal Maximum. This work provides an important framework for much-needed further paleoecological and paleoclimatic analyses into greenhouse conditions in the terrestrial Cretaceous Arctic during this important window in time.",
    url = "https://www.mdpi.com/2076-3263/14/2/36/pdf?version=1706604581",
    doi = "10.3390/geosciences14020036",
    is_oa = "true",
    number = "2",
    pages = "36",
    semanticscholar_id = "56e223bbb29f7e5afb8ed668c91d77932a2103d5",
    volume = "14"
}

@incollection{birdNonenorth,
    author = "Bird, Kenneth J.",
    title = "North Slope of Alaska",
    year = "None",
    booktitle = "Economic Geology, U.S.",
    url = "https://doi.org/10.1130/dnag-gna-p2.447",
    doi = "10.1130/dnag-gna-p2.447",
    pages = "447-462"
}