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Terrestrial Soldier Crab (Coenobita Clypeatus, Fabricius 1787) And Cerion Spp. (Röding 1798) Shell Relationship On San Salvador Island, Bahamas, Harley Hunt 2021 Georgia College

Terrestrial Soldier Crab (Coenobita Clypeatus, Fabricius 1787) And Cerion Spp. (Röding 1798) Shell Relationship On San Salvador Island, Bahamas, Harley Hunt

Biology Theses

The Caribbean terrestrial soldier crab, Coenobita clypeatus(Fabricius 1787), coexist and utilize the shells of numerous species of land and marine gastropods. Soldier crabs rely on gastropod shells for protection as the crabs have a soft abdomen, leaving them vulnerable for predation and desiccation, threatening their survival. This creates a strong pressure to obtain well-fitting shells that provide adequate protection against water loss. Cerion of Röding (1798) shells are one of the most commonly used shells among living colonies of C. clypeatuson San Salvador Island. This study is interested in the frequency of shell use by C. clypeatus crabs ...


Taphonomy Of Late Jurassic (Tithonian) Morrison Formation Apatosaurus Sp. Vertebrae Found Associated With Teeth From Allosaurus Sp. And Ceratosaurus Sp., And Body Size Extrapolation From The Associated Theropod Teeth., Greg C. Agyan 2021 Utah State University

Taphonomy Of Late Jurassic (Tithonian) Morrison Formation Apatosaurus Sp. Vertebrae Found Associated With Teeth From Allosaurus Sp. And Ceratosaurus Sp., And Body Size Extrapolation From The Associated Theropod Teeth., Greg C. Agyan

All Graduate Plan B and other Reports

An Apatosaurus sp. locality from Dinosaur National Monument designated DNM-15 was excavated in 1985, and associated with two Allosaurus teeth and one Ceratosaurus tooth that were near one of the caudal vertebrae. The Ceratosaurus tooth was buried between an overlying rib and that same caudal vertebra. The caudal vertebrae of the DNM-15 Apatosaurus were intact and articulated, but the anterior skeleton was mostly absent, with a row of articulated sacral vertebrae in close association with a femur. Two other Allosaurus teeth were reported near the preserved ilium of the Apatosaurus, but they could not be located in the collections.

Field ...


357— Dacryoconarids Of The Genundewa And West River Formations, Upper Devonian In Western New York, Emily de Jong 2021 SUNY Geneseo

357— Dacryoconarids Of The Genundewa And West River Formations, Upper Devonian In Western New York, Emily De Jong

GREAT Day

The Dacryoconarids, small, thin-walled, and cone-shaped, are an extinct taxon in Class Tentaculitoidea, which is of uncertain affinities. Dacryoconarids were widespread throughout the middle Silurian to the Late Devonian when they went extinct. This study focuses on the lower Upper Devonian Dacryoconarids of the Genundewa and West River formations from western New York State. Samples collected from these formations revealed many smooth shelled Styliolinids, however, no difinitive ribbed Dacryoconarids. Calcite was found to have internally filled in the shell of some Styliolinids, showing how thin the external shell is and raising questions about septa orientations. Due to their global occurrence ...


356— Conodonts, Microtektites, And Thermal Alteration, Of The Jefferson Formation, Upper Devonian, Wyoming, Joshua Yanuck, Ryan Lee 2021 SUNY Geneseo

356— Conodonts, Microtektites, And Thermal Alteration, Of The Jefferson Formation, Upper Devonian, Wyoming, Joshua Yanuck, Ryan Lee

GREAT Day

The Jefferson Formation, composed of two members, a limestone and dolomite dominated layer called the lower member, and the dolomite-dominated Birdbear Member, is distributed throughout southern Montana and northern Wyoming. Samples were taken from multiple levels within the Birdbear Member, dissolved in buffered 10% formic acid, and the insoluble residue separated using heavy liquid. The heavy fraction was searched for conodonts and microtektites. Conodonts indicate the Middle Frasnian stage of the Upper Devonian and thermal heating of less than 80 degrees Celsius. Microtektites, speculated to occur in the interval corresponding to the Alamo Impact in Nevada, were not found.


Rock Glen Wildlife Area: A Landscape History, Gerry Steinauer, Robert Diffendal Jr. 2021 University of Nebraska-Lincoln

Rock Glen Wildlife Area: A Landscape History, Gerry Steinauer, Robert Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nestled in the hills of southern Jefferson County, Rock Glen Wildlife Management Area, as its name implies, is a rocky land shaped by ancient geological forces, among them, meandering tropical rivers and grinding glacial ice. Euro-American settlers in the region arrived to a picturesque scene: rolling hills cloaked in tallgrass prairie fingered by glens, narrow valleys and canyons, filled with sprawling bur oaks. Too rocky to plow, southern Jefferson County has survived as an island of prairie amidst a sea of cropland. Settlement was not kind to the land. Fire suppression allowed eastern red cedars and other trees to spread ...


Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel 2021 University of Nebraska at Lincoln

Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the total volume of the High Plains Aquifer lies beneath the state. Groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Nebraska’s total groundwater resource is vast, yet it is also vulnerable to natural and anthropogenic changes, necessitating a long-term commitment to wise management through informed decision-making. Monitoring, studying, and reporting form the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.


The Lavrion Mines: A Unique Site Of Geological And Mineralogical Heritage, Panagiotis Voudouris, Vasilios Melfos, Constantinos Mavrogonatos, Adonis Photiades, Eugenia Moraiti, Branko Rieck, Uwe Kolitsch, Alexandre Tarantola, Christophe Scheffer, Denis Morin, Olivier Vanderhaeghe, Paul G. Spry, James Ross, Konstantinos Soukis, Markos Vaxevanopoulos, Igor V. Pekov, Nikita V. Chukanov, Andreas Magganas, Marianna Kati, Athanasios Katerinopoulos, Stefanos Zaimis 2021 National and Kapodistrian University of Athens

The Lavrion Mines: A Unique Site Of Geological And Mineralogical Heritage, Panagiotis Voudouris, Vasilios Melfos, Constantinos Mavrogonatos, Adonis Photiades, Eugenia Moraiti, Branko Rieck, Uwe Kolitsch, Alexandre Tarantola, Christophe Scheffer, Denis Morin, Olivier Vanderhaeghe, Paul G. Spry, James Ross, Konstantinos Soukis, Markos Vaxevanopoulos, Igor V. Pekov, Nikita V. Chukanov, Andreas Magganas, Marianna Kati, Athanasios Katerinopoulos, Stefanos Zaimis

Geological and Atmospheric Sciences Publications

The Lavrion area corresponds to the western part of the Attic-Cycladic metamorphic belt, in the back-arc region of the active Hellenic subduction zone. Between the Eocene and the Miocene, metamorphic rocks (mainly marbles and schists) underwent several stages of metamorphism and deformation due to collision and collapse of the Cycladic belt. Exhumation during the Miocene was accommodated by the movement of a large-scale detachment fault system, which also enhanced emplacement of magmatic rocks, leading to the formation of the famous Lavrion silver deposits. The area around the mines shows the stacking of nappes, with ore deposition mainly localized within the ...


Annual Report 2020 Conservation And Survey Division, Robert Matthew Joeckel 2021 University of Nebraska - Lincoln

Annual Report 2020 Conservation And Survey Division, Robert Matthew Joeckel

Conservation and Survey Division

The Conservation and Survey Division (Nebraska Geological Survey), the natural resource survey component of the School of Natural Resources, is a unique, multi-disciplinary research, service and data-collection organization established by state statute in 1921.

The Division's mission is to investigate and record information about Nebraska's geologic history, its rock and mineral resources, the quantity and quality of its water resources, land cover and other aspects of its geography, as well as the nature, distribution and uses of its soils.


African Land Mammal Ages, John Van Couvering, Eric Delson 2020 American Museum of Natural History

African Land Mammal Ages, John Van Couvering, Eric Delson

Publications and Research

We define 17 African land mammal ages, or AFLMAs, covering the Cenozoic record of the Afro-arabian continent, the planet’s second largest land mass. While fossiliferous deposits are absent on the eroded plateau of the continent’s interior, almost 800 fossil genera from over 350 locations have now been identified in coastal deposits, karst caves, and in the Neogene rift valleys. Given a well-developed geochronologic framework, together with continuing revision to the fossil record—both stimulated by the story of human evolution in Africa—and also to compensate for the variation in fossil ecosystems across such great distances, the AFLMAs ...


Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges 2020 Stephen F Austin State University

Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges

Electronic Theses and Dissertations

The Utica Shale/Point Pleasant Formation system has recently become a highly developed unconventional target for oil and natural gas production, leading to an increased desire for knowledge of the controls on deposition of this system. Precambrian basement features have long been known to affect deposition of older strata near these features across Ohio, but the effects of far field tectonics is not fully agreed upon. Precambrian faults and lineaments are known to exist and have been mapped, but are thought to have ceased their influence on deposition by the time of the Knox unconformity during the Cambrian. In the ...


Paleotectonic Investigation By Successive 3d Seismic Horizon Flattening In The Pennsylvanian Interval Of Western Osage County, Oklahoma, Douglas Cooper McCabe 2020 University of Arkansas, Fayetteville

Paleotectonic Investigation By Successive 3d Seismic Horizon Flattening In The Pennsylvanian Interval Of Western Osage County, Oklahoma, Douglas Cooper Mccabe

Theses and Dissertations

3D seismic and well log data in Western Osage County, Oklahoma, are utilized to evaluate possible intracratonic tectonic signals present in the subsurface stratigraphy of the Cherokee Platform as a result of the regional tectonic events of Pennsylvanian age. These events include: the Wichita, Ouachita, and Arbuckle orogenies, the Nemaha and Ozark Uplifts, and the Southeast Oklahoma Aulacogen. Horizon flattening within 3D seismic volumes allows for identification of paleotectonic structures and syntectonic depositional features, which may be related to the collateral effects of these orogenies on the Cherokee Platform. Identified structures were assigned geologic ages using precision synthetic seismograms tuned ...


Tributes To Rick Edwards Upon His Retirement, Robert Diffendal, Michael Farrell, Michael David Forsberg, Maurice Godfrey, John A. Janovy Jr., Katie Nieland, Linda Pratt, Rebecca S Wingo, David J. Wishart, George E. Wolf, Peter Longo, John R. Wunder 2020 University of Nebraska-Lincoln

Tributes To Rick Edwards Upon His Retirement, Robert Diffendal, Michael Farrell, Michael David Forsberg, Maurice Godfrey, John A. Janovy Jr., Katie Nieland, Linda Pratt, Rebecca S Wingo, David J. Wishart, George E. Wolf, Peter Longo, John R. Wunder

Robert F. Diffendal, Jr., Publications

I understand that you will be retiring from UNL in August. I wanted to express my sadness that you will be leaving the Center for Great Plains Studies, but am glad that you will now be able to perhaps enjoy life even more without having to do the administrative tasks that go with being the director of any organization. (RFD)


Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause 2020 East Tennessee State University

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning ...


Detrital Zircon Petrochronology For Sedimentary Provenance Analysis: Source To Sink Of The Mississippi/Missouri River Drainage Basin, Sage Denali Muttel 2020 Missouri State University

Detrital Zircon Petrochronology For Sedimentary Provenance Analysis: Source To Sink Of The Mississippi/Missouri River Drainage Basin, Sage Denali Muttel

MSU Graduate Theses

Detrital petrochronology can provide a detailed look into sedimentary provenance through integrated mineral radioisotopic ages with corresponding mineral chemistry. By combining U-Pb ages and Th/U values of detrital zircon from 13 samples collected from Quaternary sand deposits in the Upper Missouri, Yellowstone, Bighorn, Platte, Kansas, Arkansas, Mississippi, Red and Brazos Rivers, an interpretation of detailed signatures that record evidence of the evolution of the Mississippi/Missouri River drainage and the tectonic events that shaped it were observed. Low Th/U values in zircon correlate temporally to convergent magmatism, whereas, higher and more variable Th/U zircon are coeval with ...


Plate Boundary Trench Retreat And Dextral Shear Drive Intracontinental Fault-Slip Histories: Neogene Dextral Faulting Across The Gabbs Valley And Gillis Ranges, Central Walker Lane, Nevada, Jeffrey Lee, Andrew K. R. Hoxey, Andrew Calvert, Peter Dubyoski 2020 Central Washington University

Plate Boundary Trench Retreat And Dextral Shear Drive Intracontinental Fault-Slip Histories: Neogene Dextral Faulting Across The Gabbs Valley And Gillis Ranges, Central Walker Lane, Nevada, Jeffrey Lee, Andrew K. R. Hoxey, Andrew Calvert, Peter Dubyoski

All Faculty Scholarship for the College of the Sciences

The spatial-temporal evolution of intracontinental faults and the forces that drive their style, orientation, and timing are central to understanding tectonic processes. Intracontinental NW-striking dextral faults in the Gabbs Valley–Gillis Ranges (hereafter referred to as the GVGR), Nevada, define a structural domain known as the eastern Central Walker Lane located east of the western margin of the North American plate. To consider how changes in boundary type along the western margin of the North American plate influenced both the initiation and continued dextral fault slip to the present day in the GVGR, we combine our new detailed geologic mapping ...


Fayetteville And Imo Shales: Punctuated Upper Mississippian Shallowing Upward Sequence, Southern Ozark Region, Northern Arkansas, Joshua Stevens 2020 University of Arkansas, Fayetteville

Fayetteville And Imo Shales: Punctuated Upper Mississippian Shallowing Upward Sequence, Southern Ozark Region, Northern Arkansas, Joshua Stevens

Theses and Dissertations

The late Mississippian lithostratigraphic succession in the southern Ozark region, northern Arkansas, include, in ascending order, the Meramecan Moorefield Shale, Batesville Sandstone (with Hindsville Member); Chesterian Fayetteville Shale and Pitkin Limestone (with Imo Member). This interval is now interpreted as a single transgressive-regressive, unconformity-bounded, eustatic, third order cycle (Stevens and Manger, 2018). The Moorefield lowstand wedge is bound by a basal unconformity and succeeded by the transgressive Batesville Sandstone with its Hindsville Member. This succession reflects accretionary deposition along strike of the rising strand line, likely as a barrier island system, as its equivalents are shale (basinward) and limestone (laterally ...


Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson 2020 Stephen F Austin State University

Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson

Electronic Theses and Dissertations

Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.

This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the ...


Analysis Of Cryptotephra At Whitney Mesa Nature Preserve, Henderson, Nevada, Alex Newsom 2020 University of Nevada, Las Vegas

Analysis Of Cryptotephra At Whitney Mesa Nature Preserve, Henderson, Nevada, Alex Newsom

Calvert Undergraduate Research Awards

Advanced Undergraduate Winner

Cryptotephra (small volcanic shards ranging 20-80 microns in size) were discovered within Unit X of the Las Vegas Formation at Whitney Mesa Nature Preserve, Henderson, Nevada. Cryptotephra are deposited soon after a volcanic eruption and can be used as a dating tool to create narrow time constraints for surrounding sediments. Cryptotephra have many applications but are mainly useful as a dating tool. Their study has important implications for the understanding of the timing of palaeoclimatological and paleoenvironmental events as well as for archaeological studies to date important events in human history.

The Whitney Mesa cryptotephra were correlated ...


Nebraska Statewide Groundwater-Level Monitoring Report 2019, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel 2020 University of Nebraska at Lincoln

Nebraska Statewide Groundwater-Level Monitoring Report 2019, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the total volume of the High Plains Aquifer lies beneath the State. Groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Nebraska’s total groundwater resource is vast, yet it is also vulnerable to natural and anthropogenic changes, necessitating a long-term commitment to wise management through informed decision making. Monitoring, studying, and reporting form the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.

The personnel of the Conservation and Survey Division (CSD) are ...


Lithological And Geochemical Responses To Abrupt Global And Regional Paleoenvironmental Changes During The Aptian In A Hemipelagic Setting Of The Eastern Iberian Peninsula: A Multi-Proxy Approach, Jander Socorro 2020 Florida International University

Lithological And Geochemical Responses To Abrupt Global And Regional Paleoenvironmental Changes During The Aptian In A Hemipelagic Setting Of The Eastern Iberian Peninsula: A Multi-Proxy Approach, Jander Socorro

FIU Electronic Theses and Dissertations

Intense episodes of environmental perturbations and regionally to globally distributed, oxygen-deprived marine facies characterize the Cretaceous sedimentary record. The Organyà Basin in the Spanish Pyrenees chronicles this period in expanded stratigraphic sequences that enabled high-resolution sampling and detailed analysis of disturbances poorly recorded in more lithologically condensed sections. Here, I present an integrated multi-proxy study aimed at understanding the Basin’s response to changing paleoenvironmental conditions during the early Aptian stage of the Cretaceous.

Results from the El Pui section indicate that large-scale (> 1‰), negative carbon isotope excursions (CIEs) that show no corresponding shifts in local sources of organic matter ...


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