Paleontology Commons^™

Determining The Age Of A Stabilized Dune Field, Carissa Raymond

UCARE: Research Products

The aim of this project was to assess the development and age of the Kearney Dunefield in central Nebraska through the collection and analysis of sand samples from the inactive dunes. These dunes are not part of the well-known Nebraska Sandhills, and so far have not been thoroughly studied. Similar assessments have been conducted on dune fields throughout the Great Plains, and this study seeks to place the Kearney Dunes into a regional context.

The OSL ages for the Kearney cores fall between approximately 590 and 690 years ago. These dates overlap with a period of activation for the Nebraska …

Geology Of The Platte River Valley Near Kearney, Nebraska, Jeremy S. Dillon, Paul R. Hanson, Ashley Larsen, Jacob Bruihler, Carissa Raymond

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Science Ama Series: Antarctic Peninsula Paleontology Project, Matt Lamanna, Julia Clarke, Pat O'Connor, Ross Macphee, Erik Gorscak, Abby West, Chris Torres, Kerin M. Claeson, Meng Jin, Steve Salisbury, Eric Roberts, Zubair Jinnah

PCOM Scholarly Works

Transcript of an online colloquium between members of the APPP expedition and readers of the online bulletin board Reddit.

Climate, Ecology, And Human Evolution During The Plio-Pleistocene, Scott Adam Blumenthal

Dissertations, Theses, and Capstone Projects

A major goal of paleoanthropology is to identify the selective pressures associated with hominin biological and behavioral evolution, yet establishing cause-effect relationships between climate, ecology, and human evolution remains problematic. This dissertation seeks to investigate hominin paleoecology in eastern Africa by reconstructing aspects of climate and ecology using stable isotope analysis.

The first part of this dissertation is focused on the ecology of primates and hominins. Modern tropical African ecosystems provide a useful model for understanding the ecological correlates of isotopic variation in the fossil record, and living primates provide a useful model for understanding the ecological significance of isotopic …

Revision Of Polycotylid Plesioaur Systematics (Sauropterygia Plesiosauria) And Description Of The Axial Osteology Of A Juvenile Polycotylid, Donald Joseph Morgan Iii

Theses, Dissertations and Capstones

The polycotylids were a clade of plesiosaurs that proliferated during the Cretaceous period. Despite recent research efforts, evolutionary relationships among polycotylid species remain unresolved. In this study, a phylogenetic analysis incorporating a large taxon sampling from the Polycotylidae was used to parse out the evolutionary relationships among the taxa. The main focus was to assign two polycotylid specimens from the Wallace Ranch to a formal species. A study on the axial osteology of the juvenile Wallace Ranch polycotylid was also performed, as the development of the axial column of a polycotylid plesiosaur has been poorly understood and may have phylogenetic …

Analyzing Pterosaur Ontogeny And Sexual Dimorphism With Multivariate Allometry, Erick Charles Anderson

Theses, Dissertations and Capstones

The relationships of pterosaurs have been previously inferred from observed traits, depositional environments, and phylogenetic associations. A great deal of research has begun to analyze pterosaur ontogeny, mass estimates, wing dynamics, and sexual dimorphism in the last two decades. The latter has received the least attention because of the large data set required for statistical analyses. Analyzing pterosaurs using osteological measurements will reveal different aspects of size and shape variation in Pterosauria (in place of character states) and sexual dimorphism when present. Some of these variations, not easily recognized visually, will be observed using multivariate allometry methods including Principle Component …

A Dielasma Community From The Triassic Of Makhtesh Ramon, Southern Israel, Howard R. Feldman, Alexa J. Belowich

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

The cosmopolitan brachiopod Dielasma ranges from the Upper Mississippian through the Upper Triassic. In southern Israel a new Dielasma community is recognized from the Triassic Saharonim Formation, Ramon Crater. The shells represent a new species and are very strongly sulciplicated, a feature that seems to be more prevalent in the Mesozoic than the Paleozoic. The Saharonim Formation was deposited under normal, calm, relatively shallow marine conditions as part of the global transgression of the Early Ladinian sea. There is no evidence of evaporitic or dolomitic sediments. The complete absence of scouring within the carbonates or signs of channeling and ripple …

Taxonomy, Location Of Origin, And Health Status Of Proboscideans From Western Canada Investigated Using Stable Isotope Analysis, Jessica Z. Metcalfe, Fred Longstaffe, Christopher N. Jass, Grant D. Zazula, Grant Keddie

Earth Sciences Publications

We investigated the application of stable isotope analysis of proboscidean remains (collagen in bone/dentin/cementum and structural carbonate in enamel bioapatite) for genus-level identification of isolated specimens, assessment of geographic origins, and testing for nutritional stress. Mammoths (Mammuthus sp.) tended to have higher δ¹⁵N_col and lower δ¹³C_col than mastodons (Mammut americanum), but differences were not significant in every location. Determining the genus of isolated specimens may be possible for locations and time periods with good isotopic baselines, but environmental changes can confound interpretations. For example, an Alberta proboscidean with a δ¹⁵N …

Aquifers Of Nebraska I: The Codell Aquifer In Northeastern Nebraska, Dana Divine, R. Matthew Joeckel, Sue Olafsen Lackey

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Lithologic Character Of The Paleozoic Sandstone Succession, Southern Ozark Region, Arkansas, And Missouri, E. C. Bello

Journal of the Arkansas Academy of Science

Sandstones comprise nearly half of the Paleozoic (Upper Cambrian-Middle Pennsylvania) lithostratigraphic succession in the southern Ozark region of northern Arkansas and southern Missouri. They record five distinct, but related intervals characterized by 1) Upper Cambrian arkoses resting unconformably on Precambrian granite; 2) Lower Ordovician reworked subarkoses, sublitharentites, and quartzites; 3) Lower Ordovician to Lower Mississippian reworked orthoquartzites; 4) Upper Mississippian first cycle sandstones with few metamorphic rock fragments (mrfs); 5) Lower Pennsylvanian (Morrowan) first cycle sandstones with common mrfs and Middle Pennsylvanian (Atokan) first cycle sandstones with common to abundant mrfs. These sandstones accumulated on a gently sloping cratonic platform …

Age And Correlation Of The Moorefield Shale (Upper Mississippian) In Its Type Area, Northeastern Arkansas, O. Dalu, W. S. Coffey, W. L. Manger

Journal of the Arkansas Academy of Science

The name Moorefield was proposed by Adams and Ulrich (1904) for exposures of gray to brown, phosphatic shale with a basal limestone, overlying the Lower Mississippian Boone Formation, and underlying the Upper Mississippian Batesville Sandstone, in the vicinity of Moorefield, Independence County, northeastern Arkansas. Gordon (1944) 1) restricted the name Moorefield to the lower limestone-bearing interval, 2) applied a new name, Ruddell, to the succeeding shale section that comprises the bulk of the interval, with a type area near Moorefield, and 3) interpreted the interval contacts as unconformities. The name Ruddell was used for the revised Geological Map of Arkansas …

Trace Fossils From The Shawangunk Formation In The Hudson Valley Indicate An Estuarine Depositional Environment, Howard R. Feldman, Alex Bartholemew, Carlton E. Brett, Matthew B. Vrazo, Marcelo Rosensaft

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

The Middle Silurian Shawangunk Formation crops out in the lower Hudson Valley and extends toward the southwest into New Jersey and Pennsylvania. It reaches a maximum thickness around Guymard (1,400 ft.; 400m) and gradually thins toward the northeast, pinching out near Binnewater, New York. The formation consists of gray conglomerate, quartz arenite, and minor shale. Worm burrows, Arthrophycus, Skolithos, Planolites?, and a bilobed resting trace have been found at different stratigraphic horizons in the Shawangunk Formation. All traces are associated with a finer, sandy matrix and/or hematite-rich interval rather than a coarse, pebbly quartz sandstone lithology dominant in the bulk …

Regional Geochemical Mapping Of The Superior Upland Province; Ichnology Of The Cretaceous Mesilla Valley Formation, Cerro De Cristo Rey; A New Ichnospecies Of Cardioichnus From The Cretaceous (Albian) Of New Mexico; A Pedagogy For The Cerro De Cristo Rey Tracksite; Walking In The Footprints Of Dino, Eric J. Kappus

Open Access Theses & Dissertations

This is a multi-disciplinary study that covers a variety of geoscience topics on both international borders of the continental United States. This Dissertation is the product of several separate investigations. First is a report on the landscape geochemistry of the Superior Upland Province of Minnesota, Wisconsin, and Michigan, with regional maps of 37 chemical elements interpreted in terms of bedrock, glacial reworking, and anthropogenic influence. The next 2 sections are reports on the invertebrate ichnology of the Cretaceous Mesilla Valley Formation at Cerro de Cristo Rey, including the proposal of a new ichnospecies of echinoid resting trace, Cardioichnus biloba nov. …

Late Glacial And Holocene History Of The Penobscot River In The Penobscot Lowland, Maine, Roger Leb. Hooke, Paul R. Hanson, Danile F. Belknap, Alice R. Kelley

Conservation and Survey Division: Faculty and Staff Publications

When the Laurentide ice sheet retreated rapidly (~150 m/a) across the Penobscot Lowland between ~16 and ~15 ka, the area was isostatically depressed and became inundated by the sea. Silt and clay were deposited, but no significant moraines or deltas were formed. The Penobscot River was reborn at ~14 ka when ice retreated onto land in the upper reaches of the river’s East Branch. As isostatic rebound exceeded sea level rise from melting ice, the river extended itself southward. Between ~13.4 and 12.8 ka, it established a course across marine clay and underlying glacial till in the Lowland. Its gradient …

Unraveling The Consequences Of The Terminal Pleistocene Megafauna Extinction On Mammal Community Assembly, Felisa A. Smith, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Thomas W. Stafford

School of Biological Sciences: Faculty Publications

Recent studies connecting the decline of large predators and consumers with the disintegration of ecosystems often overlook that this natural experiment already occurred. As recently as 14 ka, tens of millions of large-bodied mammals were widespread across the American continents. Within 1000 yr of the arrival of humans, ∼80% were extinct including all > 600 kg. While the cause of the late Pleistocene (LP) extinction remains contentious, largely overlooked are the ecological consequences of the loss of millions of large-bodied animals. Here, we examine the influence of the LP extinction on a local mammal community. Our study site is Hall’s Cave …

Nebraska's Public Access Hunting Program: Hunter Preferences And Usage Final Report, Lisa Pennisi, Mark E. Burbach, Namyun Kil, Muhammed Imran Kahn, Andrew J. Tyre

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Department of Earth, Environment and Sustainability Faculty Publications

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …

North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S. T. Tucker

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

A New Taeniolabidoid Multituberculate (Mammalia) From The Middle Puercan Of The Nacimiento Formation, New Mexico, And A Revision Of Taeniolabidoid Systematics And Phylogeny, Thomas E. Williamson, Stephen L. Brusatte, Ross Secord, Sarah Shelley

Department of Earth and Atmospheric Sciences: Faculty Publications

Multituberculates were amongst the most abundant and taxonomically diverse mammals of the late Mesozoic and the Paleocene, reaching their zenith in diversity and body size in the Paleocene. Taeniolabidoidea, the topic of this paper, includes the largest known multituberculates, which possess highly complex cheek teeth adapted for herbivory. A new specimen from the early Paleocene (middle Puercan; biochron Pu2) of the Nacimiento Formation, New Mexico represents a new large-bodied taeniolabidoid genus and species, Kimbetopsalis simmonsae. A phylogenetic analysis to examine the relationships within Taeniolabidoidea that includes new information from Kimbetopsalis gen. et sp. nov. and gen. nov. and …

Eastern Tropical Pacific Climate And El Niño Variability During The Past Millennium, Gerald Thomas Rustic

Dissertations, Theses, and Capstone Projects

The El Niño Southern Oscillation (ENSO) has been implicated in large-scale climate shifts of the past millennia, but paleoclimate records from the dynamically vital eastern equatorial Pacific Ocean (EEP) spanning the past millennium are sparse. This has limited our understanding of tropical Pacific dynamics, leaving questions regarding the source of ENSO variability unanswered. Here I seek to address some of these questions regarding relationship between ENSO and tropical Pacific mean state, and the relationship between the tropical Pacific and large-scale climate. Mean EEP sea surface temperature (SST) for the past millennium was reconstructed using Mg/Ca ratios in Globigerinoides ruber from …