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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 ...


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 feeding patterns ...


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 2016 Nanjing University

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

Shuang-ye Wu

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 ...


Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu 2016 University of Chinese Academy of Sciences

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Shuang-ye Wu

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect ...


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

Dissertations & Theses in Earth and Atmospheric Sciences

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

Dissertations & Theses in Earth and Atmospheric Sciences

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 ...


On The Aquatic Habits Of Sauropods – An Antiquated Theory In Need Of Revival?, Michael D. Sprague 2016 Cedarville University

On The Aquatic Habits Of Sauropods – An Antiquated Theory In Need Of Revival?, Michael D. Sprague

The Research and Scholarship Symposium

When sauropods were first discovered, they were thought to have been restricted to life in the water due to their immense size. This image of sauropods was dismissed in the 1950’s when it was determined that the lungs would have been placed under massive amounts of pressure at these depths, rendering breathing nearly impossible (Kermack, 1951). However, these experiments failed to consider pneumaticity of sauropod vertebrae and were later dismissed. Sauropods possessed pneumatic features in all their presacral vertebrae, originally identified as weight-saving structures. These features kept the strength and integrity of the bone while dramatically reducing its weight ...


Microstructures Produced By Hadrosaur Bones From Alaska And Wyoming, Mark P. Guilliams, Samantha J. Lefaive, Michael D. Sprague 2016 Cedarville University

Microstructures Produced By Hadrosaur Bones From Alaska And Wyoming, Mark P. Guilliams, Samantha J. Lefaive, Michael D. Sprague

The Research and Scholarship Symposium

Since 2005 when Dr. Mary Schweitzer made the first discovery, microstructures with the appearance of “osteocytes” and “blood vessels” have been recovered from fossils of various localities, dating back as far as the Triassic. The majority of these finds have come from dense, cortical bone but recently have been discovered in cancellous bone. Since her initial discovery, Schweitzer has done a lot of work to verify that these microstructures are not biofilms, but instead are original organic tissue. This project was looking to get similar results to Schweitzer’s research and to find a simple test method for the initial ...


Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. McGrew, Kenneth A. Foland 2016 Yale University

Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland

Allen J. McGrew

New mapping, structural analysis, and 40Ar/39Ar dating reveal an unusually well‐constrained history of Late Eocene extension in the Copper Mountains of the northern Basin and Range province. In this area, the northeast‐trending Copper Creek normal fault juxtaposes a distinctive sequence of metacarbonate and granitoid rocks against a footwall of Upper Precambrian to Lower Cambrian quartzite and phyllite. Correlation of the hanging wall with footwall rocks to the northwest provides an approximate piercing point that requires 8–12 km displacement in an ESE direction. This displaced fault slice is itself bounded above by another normal fault (the Meadow ...


Determining The Age Of A Stabilized Dune Field, Carissa Raymond 2016 University of Nebraska-Lincoln

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 ...


Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera, Crystal Pletka 2016 Florida International University

Neogene Changes In Caribbean Paleoproductivity And The Diversity And Paleobiogeography Of Deep-Sea Benthic Foraminifera, Crystal Pletka

FIU Electronic Theses and Dissertations

The Neogene history of Caribbean deep-sea benthic foraminifera was investigated by calculating changes in paleoproductivity, diversity and paleobiogeography ~26 to 2 Ma, which includes the progressive closure of the Central American Seaway. Three hypotheses were tested: (1) Paleoproductivity values prior to closure of the Central American Seaway are similar in both the Caribbean and equatorial Pacific and then diverge by the time of early shoaling events; (2) Diversity values of benthic foraminifera prior to the closure of the Central American Seaway were similar in the Caribbean and EEP, and had changed by the time of early shoaling; and (3) during ...


Correspondence Of Historic Salinity Fluctuations In Florida Bay, Usa, To Atmospheric Variability And Anthropogenic Changes, Anna Wachnicka, Evelyn Gaiser, Laurel Collins 2016 Department of Earth and Environment and Southeast Environmental Research Center, Florida International University

Correspondence Of Historic Salinity Fluctuations In Florida Bay, Usa, To Atmospheric Variability And Anthropogenic Changes, Anna Wachnicka, Evelyn Gaiser, Laurel Collins

Evelyn E. Gaiser

Florida Bay is a highly dynamic estuary that exhibits wide natural fluctuations in salinity due to changes in the balance of precipitation, evaporation and freshwater runoff from the mainland. Rapid and large-scale modification of freshwater flow and construction of transportation conduits throughout the Florida Keys during the late nineteenth and twentieth centuries reshaped water circulation and salinity patterns across the ecosystem. In order to determine long-term patterns in salinity variation across the Florida Bay estuary, we used a diatom-based salinity transfer function to infer salinity within 3.27 ppt root mean square error of prediction from diatom assemblages from four ...


Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar 2016 Hydro Tasmania Consulting

Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar

Umesh K. Haritashya

Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than ...


Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe 2016 University of Colorado

Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe

Umesh Haritashya

The Chugach Mountains contain the largest nonpolar alpine glaciers in the world and include a wide variety of glacier types: some are land terminating; some calve variously into tidewater, lakes, and rivers; some are heavily debris covered; some are surge-type, whereas others are neither debris covered nor surge type. Nearly all are retreating, thinning, or both, though some rare ones are advancing, and some are thickening at high elevations. To assist the further documentation of changes, we establish an inventory of glaciers in the eastern Chugach Mountains. Several case studies of diverse glacier types showcase remotesensing applications and are used ...


Surface Scan Of The Squamosal Of Cpc 274, Brandon P. Hedrick 2016 University of Pennsylvania

Surface Scan Of The Squamosal Of Cpc 274, Brandon P. Hedrick

VP3D Scans

CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).


Surface Scan Of The Dentary Of Cpc 274, Brandon P. Hedrick 2016 University of Pennsylvania

Surface Scan Of The Dentary Of Cpc 274, Brandon P. Hedrick

VP3D Scans

CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).


Surface Scan Of The Parietal Fragment 1 Of Cpc 274, Brandon P. Hedrick 2016 University of Pennsylvania

Surface Scan Of The Parietal Fragment 1 Of Cpc 274, Brandon P. Hedrick

VP3D Scans

CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).


Surface Scan Of The Parietal Fragment 2 Of Cpc 274, Brandon P. Hedrick 2016 University of Pennsylvania

Surface Scan Of The Parietal Fragment 2 Of Cpc 274, Brandon P. Hedrick

VP3D Scans

CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).


Surface Scan Of The Premaxilla Of Cpc 274, Brandon P. Hedrick 2016 University of Pennsylvania

Surface Scan Of The Premaxilla Of Cpc 274, Brandon P. Hedrick

VP3D Scans

CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).


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