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Depositional Model Of A Late Cretaceous Dinosaur Fossil Concentration, Lance Formation, Summer Rose Weeks 2016 Loma Linda University

Depositional Model Of A Late Cretaceous Dinosaur Fossil Concentration, Lance Formation, Summer Rose Weeks

Loma Linda University Electronic Theses, Dissertations & Projects

A large Maastrichtian, nearly monospecific bonebed in the Lance Formation in eastern Wyoming has yielded 13,000 bones and fragments since 1996. Though excavation of the site continues, little is known of the circumstances and processes of deposition. This study aims to provide a depositional model for the bonebed. To accomplish this task we utilized 1D facies analysis of surrounding units and 3D analysis of the bonebed. The nature of the outcrop limited facies analysis to 1D. Four measured stratigraphic sections, each containing the bonebed unit, were taken and used in facies analysis. In addition, laterally continuous units were observed and …


Three-Dimensional Architecture And Hydrostratigraphy Of Cross-Cutting Buried Valleys Using Airborne Electromagnetics, Glaciated Central Lowlands, Nebraska, Usa, Jesse T. Korus Dr., Robert Matthew Joeckel, Dana P. Divine, Jared D. Abraham 2016 University of Nebraska-Lincoln

Three-Dimensional Architecture And Hydrostratigraphy Of Cross-Cutting Buried Valleys Using Airborne Electromagnetics, Glaciated Central Lowlands, Nebraska, Usa, Jesse T. Korus Dr., Robert Matthew Joeckel, Dana P. Divine, Jared D. Abraham

Conservation and Survey Division: Faculty and Staff Publications

Buried valleys are characteristic features of glaciated landscapes, and their deposits host important aquifers worldwide. Understanding the stratigraphic architecture of these deposits is essential for protecting groundwater and interpreting sedimentary processes in subglacial and ice-marginal environments. The relationships between depositional architecture, topography and hydrostratigraphy in dissected, pre-Illinoian till sheets is poorly understood. Boreholes alone are inadequate to characterize the complex geology of buried valleys, but airborne electromagnetic surveys have proven useful for this purpose. A key question is whether the sedimentary architecture of buried valleys can be interpreted from airborne electromagnetic profiles. This study employs airborne electromagnetic resistivity profiles to …


Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang 2016 University of Nebraska-Lincoln

Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Members of the family Rhinocerotidae first appeared in the middle Eocene and were one of most successful mammal groups of the Oligocene and Miocene in North America. Their extinction in the early Pliocene has been attributed to several causes, including cooling climate, an expansion of C4 grasslands, and faunal turnover favoring high-crowned, open habitat-adapted mammalian taxa. This study tests whether the extinction of North American rhinoceroses in the Great Plains was abrupt or gradual by examining changes in their paleogeographic distribution in a series of time-slices through the Barstovian, Clarendonian, and Hemphillian North American land-mammal ages. It further examines …


Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West 2016 University of South Florida

Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West

USF Tampa Graduate Theses and Dissertations

Mollusk shells contain proteins within and between the crystals of calcium carbonate. These organic molecules play an important role in biomineralization and shell function, and their stable isotope ratios of carbon and nitrogen are also thought to record important ecological information about the animal's diet and nutrient sources. These proteins can be preserved for millions of years, offering potential insight into pre-anthropogenic ecological conditions. However, shell organics in older shells are typically recovered in reduced abundances due to leaching and remaining organics are often converted from insoluble proteins to soluble, free amino acids, making them difficult to detect and recover. …


The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson 2016 Loma Linda University

The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure of carbonate rocks within the uplifted mountains of southwestern Utah presents a unique opportunity to study the growth, morphology and ecology of two upper Cambrian microbialite reefs located within the Hellnmaria Member of the Notch Peak Formation. The first reef contains meter-length, strongly elongate microbialites that grew in a deep, subtidal marine environment. These elongate microbialites formed as a result of coalescence of round ‘algal’ heads, a process known to produce compound microbialite structures in shallow water, but seldom explored as a key factor in the elongation of deep, subtidal forms that grew in ancient environments. The second reef …


Taphonomy Of A Lance Formation(Maastrichtian, Wy) Dinosaur Bonebed With A Focus On Tooth Traces, Matthew A. McLain 2016 Loma Linda University

Taphonomy Of A Lance Formation(Maastrichtian, Wy) Dinosaur Bonebed With A Focus On Tooth Traces, Matthew A. Mclain

Loma Linda University Electronic Theses, Dissertations & Projects

The Rose Quarry bonebed found in the Maastrichtian Lance Formation of eastern Wyoming possesses a complex blendof taphonomic signatures. Disarticulated, disassociated, fragmented bones of various states of abrasion from dinosaurs, turtles, and crocodilians are clustered together in a channelized sandstone unit. The mismatched taphonomic signatures of the bonebed suggest that it is amixed assemblage, containing bones with different taphonomic histories that were washed together by a flood event. Sedimentological data,includingthe presence of large mud clasts in the bonebed,agree well with this hypothesis. The abundant breakage of the bones in the Rose Quarry bonebed is attributed mainly to trampling. This study …


The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu 2016 University of Nebraska-Lincoln

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Department of Earth and Atmospheric Sciences: Faculty Publications

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover …


The First Hominin From The Early Pleistocene Paleocave Of Haasgat, South Africa, AB Leece, Anthony D T Kegley, Rodrigo S. Lacruz, Andy I R Herries, Jason Hemingway, Lazarus Kgasi, Stephany Potze, Justin W. Adams 2016 La Trobe University

The First Hominin From The Early Pleistocene Paleocave Of Haasgat, South Africa, Ab Leece, Anthony D T Kegley, Rodrigo S. Lacruz, Andy I R Herries, Jason Hemingway, Lazarus Kgasi, Stephany Potze, Justin W. Adams

Peer Reviewed Articles

Haasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered from an ex situ calcified sediment block sampled from the locality. The in situ fossil bearing deposits of the Haasgat paleokarstic deposits are estimated to date to slightly older than 1.95 Ma based on magnetobiostratigraphy. This places the hominin specimen at a critical time period in South Africa that marks the last occurrence of Australopithecus around 1.98 Ma and the …


Age Re-Assessment Of The Cave Bear Assemblage From Urşilor Cave, North-Western Romania, Marius V. Robu 2016 "Emil Racoviţă" Institute of Speleology

Age Re-Assessment Of The Cave Bear Assemblage From Urşilor Cave, North-Western Romania, Marius V. Robu

International Journal of Speleology

The most common methods used for assessing the relative age of a cave bear bone assemblage are the P4/4 index (morphodynamic index of the cave bear fourth premolar), the K-index and the Index of Plumpness (both used for cave bear’s 2nd metatarsal). Preliminary work on this (Robu et al., 2011), for Urşilor Cave (NW Romania), has indicated one of the youngest European cave bear populations. As the number of extracted fossil bones from the palaeontological excavation increased recently, a re-assessment of the of the age of the cave bear assemblage is necessary. 206 cave bear fourth …


The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson 2016 Stephen F. Austin State University

The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson

Electronic Theses and Dissertations

The stratigraphy of the Pojoaque Member of the Tesuque Formation near Española, NM is not well understood. This region, during the Middle Miocene, represented a dynamic alluvial fan-fluvial-lacustrine environment within the Española Basin while the Rio Grande Rift was active. Cavazza (1986) identified two paleodrainage systems (lithosome A, basin-margin facies and B, basin-floor facies) by means of sandstone and conglomerate petrology, paleocurrent, and sedimentary facies analyses. After x-ray diffraction analyses of claystones within lithosome B, mordenite was discovered, which is a zeolite mineral commonly found within volcanic rocks. This is significant because the presence of mordenite confirms Cavazza’s (1986) conclusion …


Testing Of The Late-Ordovician Pre-Gice Warm Water Carbonate Hypothesis In Alabama, Brandon Euker, Stacey Law 2016 James Madison University

Testing Of The Late-Ordovician Pre-Gice Warm Water Carbonate Hypothesis In Alabama, Brandon Euker, Stacey Law

Senior Honors Projects, 2010-2019

The Guttenberg Carbon Isotope Excursion (GICE) (uppermost Sandbian-lower Katian, Late Ordovician) has been suggested to represent the transition from a Cambrian-Ordovician greenhouse world to Late Ordovician icehouse world. This transition is thought to coincide with a proposed shift from deposition of warm water carbonate rocks to cool water carbonate rocks in the North American midcontinent. We used oxygen isotopes (d18O) of conodonts to test the idea that the rocks below the GICE interval represent a consistently warm environment. Conodonts were isolated from samples of the Chickamauga Group collected at the Tidwell Hollow section in Blount County, AL, from …


Anatomical Markers For Elevated Cognition In Dinosaurs, Thomas Gaetano 2016 Bowling Green State University

Anatomical Markers For Elevated Cognition In Dinosaurs, Thomas Gaetano

Honors Projects

Much research has been conducted on brain evolution within Dinosauria. Dinosaurs were originally believed to be incapable of any advanced cognitive abilities beyond the level observed in modern reptiles. This is likely true for many dinosaurs, but recent discoveries suggest that the non-avian maniraptor dinosaurs shared many physical characteristics with their bird descendants, including body feathers and neural adaptations for flight. By studying cranial endocasts (the braincase of fossilized skulls) using computed tomography (CT), paleontologists are beginning to understand the neural changes that took place across the dinosaur-bird transition. Most of these studies are focused on the development of flight, …


Introduction To Paleontology Research Through The Boudreaux Bend Project, Jonathan D. Eisenhour, Abraham S. Mollett, Jennifer M. K. O'Keefe 2016 Morehead State University

Introduction To Paleontology Research Through The Boudreaux Bend Project, Jonathan D. Eisenhour, Abraham S. Mollett, Jennifer M. K. O'Keefe

Celebration of Student Scholarship Poster Sessions Archive

No abstract provided.


11th New World Luminescence Dating Workshop Scientific Program And Abstracts And Field Trip Guide Book, P.R. Hanson, James B. Swinehart, Joseph Mason 2016 University of Nebraska - Lincoln

11th New World Luminescence Dating Workshop Scientific Program And Abstracts And Field Trip Guide Book, P.R. Hanson, James B. Swinehart, Joseph Mason

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Peccaries (Artiodactyla: Tayassuidae) From The Late Miocene To Early Pliocene Gray Fossil Site: Regional Implications With A Review Of Tayassuinae, Evan M. Doughty 2016 East Tennessee State Universtiy

Peccaries (Artiodactyla: Tayassuidae) From The Late Miocene To Early Pliocene Gray Fossil Site: Regional Implications With A Review Of Tayassuinae, Evan M. Doughty

Electronic Theses and Dissertations

Analysis of the Gray Fossil Site peccary material indicates the presence of up to three species. Comparisons with the tayassuid material known from the Tyner Farm and Bone Valley Formation of Florida allows the identification of Mylohyus elmorei and at the GFS. Within the GFS material, Prosthennops cf. P. serus and cf. Catagonus sp. are also tentatively recognized but further verification is required. The known range for Prosthennops is expanded into the Appalachian region. Presence of M. elmorei at the Gray Fossil Site provides the first known occurrence of this species outside of the Palmetto fauna of Florida, indicating that …


Description Of Cranial Elements And Ontogenetic Change Within Tropidolaemus Wagleri (Serpentes: Crotalinae)., Nicolette L. Hill 2016 East Tennessee State Universtiy

Description Of Cranial Elements And Ontogenetic Change Within Tropidolaemus Wagleri (Serpentes: Crotalinae)., Nicolette L. Hill

Electronic Theses and Dissertations

Tropidolaemus wagleri is a species of Asian pitviper with a geographic range including Thailand, Vietnam, Malaysia, Singapore, Bruniei, parts of Indonesia, and the hilippines. Tropidolaemus is a member of the Crotalinae subfamily, within Viperidae. The genus Tropidolaemus includes five species, and was once included within the genus Trimeresurus. While some osteologic characteristics have been noted a comprehensive description of cranial elements has not been produced for T. wagleri. An in-depth description of the cranial skeleton of Tropidolaemus wagleri lays the foundation for future projects to compare and contrast other taxa within Crotalinae and Viperidae. The chosen reference specimen …


Description, Taphonomy, And Paleoecology Of The Late Pleistocene Peccaries (Artiodactyla: Tayassuidae) From Bat Cave, Pulaski County, Missouri, Aaron L. Woodruff 2016 East Tennessee State University

Description, Taphonomy, And Paleoecology Of The Late Pleistocene Peccaries (Artiodactyla: Tayassuidae) From Bat Cave, Pulaski County, Missouri, Aaron L. Woodruff

Electronic Theses and Dissertations

The late Pleistocene faunal assemblage from Bat Cave, central Ozarks, Missouri provides an opportunity to assess specific aspects of behavior, ecology, and ontogeny of the extinct peccary Platygonus compressus. All identifiable elements referable to this taxon were catalogued and examined, and a minimum number of individuals of 70 was determined for the sample. The presence of distinct, non-overlapping age groups suggests that P. compressus utilized Bat Cave on a seasonal basis. A predator-prey relationship with Canis dirus, the second most abundant vertebrate from the Bat Cave site, is also described in this study. Damage patterns suggest that the …


New Records Of Colubrids From The Late Hemphillian Gray Fossil Site Of Northeastern Tennessee, Derek J. Jurestovsky 2016 East Tennessee State University

New Records Of Colubrids From The Late Hemphillian Gray Fossil Site Of Northeastern Tennessee, Derek J. Jurestovsky

Electronic Theses and Dissertations

The Gray Fossil Site is a rich Hemphillian (North American Land Mammal Age) locality located in northeastern Tennessee which has produced tens-of-thousands of fossils of multiple taxa including hundreds of individual snake skeletal remains. Analyzed here are cranial and vertebral fossils identified as belonging to various colubrid taxa including Carphophis sp., Gyalopion sp., Heterodon sp., Natricinae indeterminate, Thamnophis sp., and a new, undescribed genus and species. In addition, multiple new features of snake vertebrae are described, some of which question the validity of the genus Neonatrix. Finally, the distribution and paleoecology of the listed genera allows an interpretation of …


Upper Albian To Lower Cenomanian Calcareous Nannofossil Biostratigraphy Of The Proto-North Atlantic, Shamar Chin 2016 University of Nebraska-Lincoln

Upper Albian To Lower Cenomanian Calcareous Nannofossil Biostratigraphy Of The Proto-North Atlantic, Shamar Chin

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Lower Cenomanian calcareous nannofossil assemblages from Deep Sea Drilling Project (DSDP) Sites 137 and 547 in the proto-North Atlantic Ocean were analyzed quantitatively to examine the fidelity of the widely used CC and UC calcareous nannofossil Zonal schemes. Datasets from Ocean Drilling Program (ODP) holes 1050C and 1052E (Blake Nose) and Tanzania Drilling Project (TDP) Site 24 were integrated into this dataset. Four biozones spanning the upper Albian through middle Cenomanian were determined using the method of unitary associations (UA). Data were also used from these sequences to generate a ranking and scaling (RASC) optimum sequence. A new reliability index …


Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator, Evan Whiting 2016 University of Nebraska-Lincoln

Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator, Evan Whiting

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Most amphibians and reptiles (excluding birds) are poikilothermic; their internal body temperature varies with that of their external environment. This makes them useful as climate proxies, especially when linked to geographic distributions of ambient climate. I evaluate the utility of the extant crocodylian genus Alligator as a paleoclimate proxy for the Central Great Plains (CGP) using species distribution modeling. Alligator is a readily identifiable taxon with a good CGP fossil record during the Neogene (~23–2.6 Ma). Alligator first appeared in the CGP in the late Eocene (~37 Ma), was absent during most of the Oligocene, reappeared in the early Miocene …


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