Related Papers
Paleontology of Bears Ears National Monument (Utah, USA)
2020 •
jessica uglesich
Bears Ears National Monument (BENM) is a new landscape-scale national monument in southeastern Utah, jointly administered by the Bureau of Land Management and the U.S. Forest Service as part of the National Conservation Lands system. As initially designated in 2016, BENM encompassed 1.3 million acres of land with exceptionally fossiliferous rock units. Subsequently, in December 2017, presidential action reduced BENM to two smaller management units (Indian Creek and Shash Jaa). Although the paleontological resources of BENM are extensive and abundant, they have historically been under-studied. Herein we summarize prior paleontological work within the original BENM boundaries to provide a more comprehensive picture of the known paleontological resources, which are used to support paleontological resource protection. The fossil-bearing units in BENM comprise a nearly continuous depositional record from aproximately the Middle Pennsylvanian Period (about 310 Ma) through the middle of th...
Geology of the Intermountain West
PALEONTOLOGY OF BEARS EARS NATIONAL MONUMENT (UTAH, USA)- HISTORY OF EXPLORATION, STUDY, AND DESIGNATION
2020 •
Robert Gay
Bears Ears National Monument (BENM) is a new landscape-scale national monument in southeastern Utah, jointly administered by the Bureau of Land Management and the U.S. Forest Service as part of the National Conservation Lands system. As initially designated in 2016, BENM encompassed 1.3 million acres of land with exceptionally fossiliferous rock units. Subsequently, in December 2017, presidential action reduced BENM to two smaller management units (Indian Creek and Shash Jáá). Although the pa-leontological resources of BENM are extensive and abundant, they have historically been under-studied. Herein we summarize prior paleontological work within the original BENM boundaries to provide a more comprehensive picture of the known paleontological resources, which are used to support paleontological resource protection. The fossil-bearing units in BENM comprise a nearly continuous depositional record from aproximately the Middle Pennsylvanian Period (about 310 Ma) through the middle of the Cretaceous Period (about 115 Ma). Pleistocene and Holocene deposits are known from unconsolidated fluvial terraces and cave deposits. The fossil record from BENM provides unique insights into several important pale-ontological intervals of time including the Carboniferous-Permian icehouse-greenhouse transition and evolution of fully terrestrial tetrapods, the rise of the dinosaurs following the end-Triassic mass extinction, and the response of ecosystems in dry climates to sudden temperature increases at the end of the last glacial maximum.
New Mexico Museum of Natural History and Science Bulletin
First report of "Chirotherium" lulli from the Upper Triassic Chinle Formation of San Juan County, Utah
2021 •
Andrew Milner
We report the first occurrence of the track type "Chirotherium" lulli from western North America.
Lithostratigraphy and biostratigraphy of the Chinle Formation (Upper Triassic) in southern Lisbon Valley, southeastern Utah
Andrew Milner
ABSTRACT We present here a detailed study of the lithostratigraphy and preliminary vertebrate biostratigraphy of the Upper Triassic Chinle Formation in Lisbon Valley, southeastern Utah. Triassic salt tectonism resulted in a period of erosion and possibly non-deposition that removed the top of the Lower Permian Cutler Group, the Early-Middle Triassic Moenkopi Formation, and the Late Triassic (earliest Norian) Shinarump Member of the Chinle Formation. Chinle Formation deposition in Lisbon Valley began or resumed sometime during the middle-late Norian or Rhaetian and terminated before the end of the Rhaetian. Chinle Formation sediments are mostly siltstone to fine-grained sandstone dominated by planar cross-bedding and climbing ripple cross-lamination; these sediments generally exhibit poor paleosol development, with interbedded conglomerates dominated by clasts composed of reworked intrabasinal sediments and containing only minor extrabasinal silica. The regional climate during Chinle deposition was becoming increasingly arid, with fluctuating seasonal rainfall. Deposition by the braided and meandering rivers of the lower Kane Springs beds filled paleovalleys incised into the Cutler Group, and was followed by a poorly drained interval of poorly oxygenated swamps and lakes crisscrossed by small streams that produced the middle Kane Springs beds. These conditions transitioned back to the slowly aggrading braided and meandering rivers of the upper Kane Springs beds, probably by Rhaetian time. The Kane Springs paleoenvironment, probably at least partially syndepositional with that of the Owl Rock Member, was inhabited by conifers, freshwater ostracods, bivalves and gastropods, indeterminate phytosaurs, and the aetosaur Typothorax. The shift to the overlying Church Rock Member was gradational and probably involved only subtle shifts in the depositional system, largely related to better-drained sediments. Braided channels with seasonally variable discharge crossed well-drained, rapidly aggrading and well-oxygenated floodplains. Rare paleosols (including entisols, vertisols, and aridisols) indicate seasonal wetting and drying in a generally arid climate. Rivers and lakes were inhabited by the phytosaur taxon Machaeroprosopus (including the derived form “Redondasaurus”), rare metoposaurids, coelacanths, a diverse actinopterygian fish fauna, conchostracans, ostracods, bivalves, and gastropods. The flora included conifer trees, giant horsetails, Cynepteris (a fern), Zamites (a bennettitalean), the small shrub-like conifer Pelourdea, and the enigmatic Sanmiguelia. Terrestrial tetrapods included the aetosaur Typothorax (suggesting that the genus endured into the Rhaetian), paracrocodylomorphs, and small theropods. Eventually, wind-blown eolian deposits entered the region, and late in the Rhaetian, prior to 201.3 Ma, the eolian Wingate erg swamped small braided channels still inhabited by the phytosaur “Redondasaurus,” actinopterygian fishes, and small theropods.
UPPER TRIASSIC LITHOSTRATIGRAPHY, DEPOSITIONAL SYSTEMS, AND VERTEBRATE PALEONTOLOGY ACROSS SOUTHERN UTAH A Field Guide Prepared For SOCIETY OF VERTEBRATE PALEONTOLOGY
James Kirkland, Andrew Milner, Vincent Santucci
e Chinle Formation and the lower part of the overlying Wingate Sandstone and Moenave Formation were deposited in uvial, lacustrine, paludal, and eolian environments during the Norian and Rhaetian stages of the Late Triassic (~230 to 201.3 Ma), during which time the climate shied from subtropical to increasingly arid. In southern Utah, the Shinarump Member was largely conned to pre-Chinle pale-ovalleys and usually overprinted by mottled strata. From southeastern to southwestern Utah, the lower members of the Chinle Formation (Cameron Member and correlative Monitor Butte Member) thicken dramatically whereas the upper members of the Chinle Formation (the Moss Back, Petried Forest, Owl Rock, and Church Rock Members) become erosionally truncated; south of Moab, the Kane Springs beds are laterally correlative with the Owl Rock Member and uppermost Petried Forest Member. Prior to the erosional truncation of the upper members, the Chinle Formation was probably thickest in a southeast to northwest trend between Petried Forest National Park and the Zion National Park, and thinned to the northeast due to the lower Chinle Formation lensing out against the anks of the Ancestral Rocky Moun-tains, where the thickness of the Chinle is largely controlled by syndepositional salt tectonism. e Gartra and Stanaker Members of the Ankareh Formation are poorly understood Chinle Formation correlatives north of the San Rafael Swell. Osteichthyan sh, metoposaurid temnospondyls, phytosaurids, and croco-dylomorphs are known throughout the Chinle Formation, although most remains are fragmentary. In the Cameron and Monitor Butte Members, metoposaurids are abundant and non-pseudopalatine phytosaurs are known, as is excellent material of the paracrocodylomorph Poposaurus; fragmentary specimens of the aetosaurs Calyptosuchus, Desmatosuchus, and indeterminate paratypothoracisins were probably also recovered from these beds. Osteichthyans, pseudopalatine phytosaurs, and the aetosaur Ty pothorax are es-pecially abundant in the Kane Springs beds and Church Rock Member of Lisbon Valley, and Ty pothorax is also known from the Petried Forest Member in Capitol Reef National Park. Procolophonids, doswelliids, and dinosaurs are known but extremely rare in the Chinle Formation of Utah. Body fossils and tracks of osteichthyans, therapsids, crocodylomorphs, and theropods are well known from the lowermost Wingate Sandstone and Moenave Formation, especially from the St. George Dinosaur Discovery Site at Johnson Farm.
Geology of the Intermountain West
Upper Triassic lithostratigraphy, depositional systems, and vertebrate paleontology across southern Utah
2017 •
Andrew Milner
The Chinle Formation and the lower part of the overlying Wingate Sandstone and Moenave Formation were deposited in fluvial, lacustrine, paludal, and eolian environments during the Norian and Rhaetian stages of the Late Triassic (~230 to 201.3 Ma), during which time the climate shifted from subtropical to increasingly arid. In southern Utah, the Shinarump Member was largely confined to pre-Chinle paleovalleys and usually overprinted by mottled strata. From southeastern to southwestern Utah, the lower members of the Chinle Formation (Cameron Member and correlative Monitor Butte Member) thicken dramatically whereas the upper members of the Chinle Formation (the Moss Back, Petrified Forest, Owl Rock, and Church Rock Members) become erosionally truncated; south of Moab, the Kane Springs beds are laterally correlative with the Owl Rock Member and uppermost Petrified Forest Member. Prior to the erosional truncation of the upper members, the Chinle Formation was probably thickest in a south...
GEOLOGY OF THE INTERMOUNTAIN WEST UPPER TRIASSIC LITHOSTRATIGRAPHY, DEPOSITIONAL SYSTEMS, AND VERTEBRATE PALEONTOLOGY ACROSS SOUTHERN UTAH A Field Guide Prepared For SOCIETY OF VERTEBRATE PALEONTOLOGY
James Kirkland, Andrew Milner, Vincent Santucci
The Chinle Formation and the lower part of the overlying Wingate Sandstone and Moenave Formation were deposited in fluvial, lacustrine, paludal, and eolian environments during the Norian and Rhaetian stages of the Late Triassic (~230 to 201.3 Ma), during which time the climate shifted from subtropical to increasingly arid. In southern Utah, the Shinarump Member was largely confined to pre-Chinle paleovalleys and usually overprinted by mottled strata. From southeastern to southwestern Utah, the lower members of the Chinle Formation (Cameron Member and correlative Monitor Butte Member) thicken dramatically whereas the upper members of the Chinle Formation (the Moss Back, Petrified Forest, Owl Rock, and Church Rock Members) become erosionally truncated; south of Moab, the Kane Springs beds are laterally correlative with the Owl Rock Member and uppermost Petrified Forest Member. Prior to the erosional truncation of the upper members, the Chinle Formation was probably thickest in a southeast to northwest trend between Petrified Forest National Park and the Zion National Park, and thinned to the northeast due to the lower Chinle Formation lensing out against the flanks of the Ancestral Rocky Mountains, where the thickness of the Chinle is largely controlled by syndepositional salt tectonism. The Gartra and Stanaker Members of the Ankareh Formation are poorly understood Chinle Formation correlatives north of the San Rafael Swell. Osteichthyan fish, metoposaurid temnospondyls, phytosaurids, and crocodylomorphs are known throughout the Chinle Formation, although most remains are fragmentary. In the Cameron and Monitor Butte Members, metoposaurids are abundant and non-pseudopalatine phytosaurs are known, as is excellent material of the paracrocodylomorph Poposaurus; fragmentary specimens of the aetosaurs Calyptosuchus, Desmatosuchus, and indeterminate paratypothoracisins were probably also recovered from these beds. Osteichthyans, pseudopalatine phytosaurs, and the aetosaur Typothorax are especially abundant in the Kane Springs beds and Church Rock Member of Lisbon Valley, and Typothorax is also known from the Petrified Forest Member in Capitol Reef National Park. Procolophonids, doswelliids, and dinosaurs are known but extremely rare in the Chinle Formation of Utah. Body fossils and tracks of osteichthyans, therapsids, crocodylomorphs, and theropods are well known from the lowermost Wingate Sandstone and Moenave Formation, especially from the St. George Dinosaur Discovery Site at Johnson Farm.
Geology of Utah’s Parks and Monuments 2010 Utah Geological Association Publication 28 (third edition)
An Overview of National Park Service Paleontological Resources from the Parks and Monuments in Utah
2010 •
James Kirkland
The National Park Service (NPS) administers thirteen park units within the state of Utah. Most of these parks, monuments, and other NPS units have been established and are recognized for their significant geologic features. Fossiliferous rocks of Paleozoic, Mesozoic, and Cenozoic age have been identified in all of the National Park System units in Utah. In 1998, the first comprehensive inventory of paleontological resources in the national parks and monuments of Utah was initiated. A wide diversity of fossilized plants, invertebrates, vertebrates, and trace fossils has been documented. Paleontological resources identified from within the parks and monuments have been assessed relative to their scientific significance, potential threats, and management as non-renewable resources. Considerable focus has been directed towards the in situ management of the abundant fossil vertebrate tracks identified throughout the Mesozoic formations within at least seven NPS areas in Utah. The baseline paleontological resource data obtained during this inventory will assist park staff with improved management of their paleontological resources and protection of fossils within their park.
Field Trip Guide Book, 71st Annual Meeting of the Society of Vertebrate Paleontology, Paris Las Vegas, Las Vegas, Nevada, November 2-5, 2011
TRACKING EARLY JURASSIC DINOSAURS ACROSS SOUTHWESTERN UTAH AND THE TRIASSIC-JURASSIC TRANSITION
2013 •
James Kirkland
Vertebrate Paleontology in Arizona: New Mexico Museum of Natural History and Science, Bulletin
Triassic vertebrate fossils in Arizona
2005 •
Adrian Hunt
Abstract—The Triassic System in Arizona has yielded numerous world-class fossil specimens, including numerous type specimens. The oldest Triassic vertebrates from Arizona are footprints and (largely) temnospondyl bones from the Nonesian (Early Triassic: Spathian) Wupatki Member of the Moenkopi Formation. The Perovkan (early Anisian) faunas of the Holbrook Member of the Moenkopi Formation are exceptional in that they yield both body-and trace fossils of Middle Triassic vertebrates and are almost certainly the best- ...
