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Palynology And Paleoclimatology Of The Chicxulub Impact Crater In The Early Paleogene, Vann Smith 2021 Louisiana State University and Agricultural and Mechanical College

Palynology And Paleoclimatology Of The Chicxulub Impact Crater In The Early Paleogene, Vann Smith

LSU Doctoral Dissertations

At the end of the Cretaceous Period, a large bolide impacted the Earth and formed the Chicxulub impact crater in the Yucatán Peninsula, Mexico. In 2016, International Ocean Discovery Program (IODP) Expedition 364 Site M0077 drilled into the buried peak ring of the crater, recovering a marine Paleocene to early Eocene post-impact section deposited on top of the impact breccia. Palynological analysis of 195 samples from the post-impact section has yielded the first pre-Holocene vegetational record from inside the Chicxulub impact crater and the first palynological record of the recovery of life following the end-Cretaceous mass extinction from inside the …


New Perspectives On Prolific And Voluminous Rhyolite Volcanism Of The Mahogany Mountain--Three Fingers Rhyolite Field, Eastern Oregon, Robert Andrew Jackson 2021 Portland State University

New Perspectives On Prolific And Voluminous Rhyolite Volcanism Of The Mahogany Mountain--Three Fingers Rhyolite Field, Eastern Oregon, Robert Andrew Jackson

Dissertations and Theses

Voluminous silicic volcanism of the Mahogany Mountain--Three Fingers rhyolite field (MM--TFrf) is spatially and temporally associated with mid-Miocene flood basalts of the Columbia River Basalt province. Early studies of the area advocated for a two-caldera model consisting of the Mahogany Mountain and the slightly younger Three Fingers caldera with pre- and post-caldera effusive rhyolite eruptions. Although close in time, the calderas were thought to be spatially offset producing the tuff of Leslie Gulch and the tuff of Spring Creek. Finding that the tuff of Spring Creek, that is exposed in Leslie Gulch, is an altered product of the tuff of …


Ductile And Brittle Deformation Of Slackwater Deposits In The Tucannon River Valley, Chelsi K. Howard 2021 Eastern Washington University

Ductile And Brittle Deformation Of Slackwater Deposits In The Tucannon River Valley, Chelsi K. Howard

Geosciences Student Work

The Tucannon River valley in eastern Washington is home to a number of ductile and brittle soft-sediment deformation. This project aims to look at ductile deformation by classifying and comparing styles of clastic dikes in the field and to look at brittle deformation by analyzing small faults in localized outcrops. Clastic dikes are sedimentary intrusions into other sedimentary strata. There are three main types of clastic dikes: injection, extrusion, and sugtrusion. In addition, two subcategories of clastic dikes are described as sheeted dikes and fault injection dikes. Ductile and brittle deformation occurs in “slackwater” deposits associated with margins of glacial …


Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers 2021 Stephen F. Austin State University

Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers

Electronic Theses and Dissertations

The Late Cretaceous Blossom Sand within the Austin Group is a historic gas reservoir in the East Texas basin, located at depths of approximately 2,000 ft below the surface. Since the discovery of the Carthage Field in 1918 in the East Texas Basin, the Blossom Sand has produced approximately 26 BCF of gas with minor amounts of oil. Despite its notoriety in the Carthage Field, there is very little research that has been conducted on this unit, although it crops out in northeast Texas and is found in the subsurface of southwest Arkansas, western Louisiana, and the East Texas Basin. …


Linking Human Activities To Water Quality In Coastal New England: Past And Present, Amelia Hurst 2021 University of Connecticut

Linking Human Activities To Water Quality In Coastal New England: Past And Present, Amelia Hurst

University Scholar Projects

This project examines the timing and effect of direct and indirect anthropogenic and natural influences on the marine environment in embayments in southern New England over the past decades to century timescale. We investigated the effects of human land use from colonial through post-industrial times, determined baseline conditions and natural climatic variability, and analyzed the response of marine ecosystems to specific local management actions aimed to improve water quality. A coastal sediment core was taken in Mumford Cove, CT and was analyzed downcore for eutrophication markers (C: N, %C, %N, d15N, d13C) and metals (Hg, Pb, …


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, Spring 1920 to Spring 2023

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. …


Biis: The Last British Ice Sheet, A Review Of The Most Recent Major Glaciation Of Great Britain And Ireland, Benediktas Gaskevicius 2021 Wayne State University

Biis: The Last British Ice Sheet, A Review Of The Most Recent Major Glaciation Of Great Britain And Ireland, Benediktas Gaskevicius

Honors College Theses

The British Irish Ice Sheet was a substantial ice mass covering the British Isles during the most recent glaciation that ended around 11,700 years ago. Oftentimes referred to as the BIIS, it is subdivided into two sections, a western and eastern side that covered Great Britain and Ireland, with the Irish basin in the middle. Some notable areas of study around Great Britain and Ireland include the ’Bizzle’ in Northern England, which was transformed by the effects of the eastern margin of the BIIS, the Carstair Kames in Scotland, a locality known internationally for its esker system, The Minch region …


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 Posters

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.


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 Posters

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, …


Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi 2021 University of New Mexico

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi

Earth and Planetary Sciences ETDs

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …


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-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: Faculty and Staff Publications

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.


Characterizing The Geomagnetic Field At High Southern Latitudes: Evidence From The Antarctic Peninsula, Joseph Biasi, Joseph Kirschvink, Roger Fu 2021 Dartmouth College

Characterizing The Geomagnetic Field At High Southern Latitudes: Evidence From The Antarctic Peninsula, Joseph Biasi, Joseph Kirschvink, Roger Fu

Other Staff Materials

Due to a dearth of data from high-latitude paleomagnetic sites, it is not currently clear if the geocentric axial dipole (GAD) hypothesis accurately describes the long-term behavior of the geomagnetic field at high latitudes. Here we present new paleomagnetic and paleointensity data from the James Ross Island (JRI) volcanic group, located on the Antarctic Peninsula. This data set addresses a notable lack of data from the 60°–70°S latitude bin and includes 251 samples from 31 sites, spanning 0.99–6.8 Ma in age. We also include positive fold, conglomerate, and baked contact tests. Paleointensity data from three methods (Thellier- Thellier, pseudo-Thellier, and …


New Hampshire And Vicinity Continental Shelf: Sand And Gravel Resources, Larry G. Ward, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire, Durham

New Hampshire And Vicinity Continental Shelf: Sand And Gravel Resources, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) has extensive marine-modified glacial deposits and associated shoals. These features are potential targets for sand and gravel resources for beach nourishment and other efforts to build coastal resiliency. The distribution of sand and gravel deposits was evaluated based on the synthesis of relatively recent high-resolution bathymetry, new surficial sediment and geoform maps, and an extensive data archive that includes over ~1280 km of seismic profiles, ~750 grain size analyses, and 23 vibracores. This work heavily utilizes the results of previous research on mineral resources on the NH shelf by Birch (1984) …


Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire, Durham

Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

During this study, the twenty-three vibracores taken in 1984 and 1988 were reexamined, original descriptions verified and significantly expanded, and the cores sampled to provide complete grain size data (i.e. the original sediment grain size analyses were limited). The vibracores were grouped by location with respect to major physiographic features (geoforms) or surficial sediment type including Offshore Marine-Modified Glacial Features (Drumlins and Lodgement Till Deposits), Northern Sand Body, Isles of Shoals, Nearshore Marine-Modified Glacial Features (Eskers and Drumlins), Nearshore Sheet Sand, and Offshore Seafloor Plain.

The Northern Sand Body (NSB), located near the Isles of Shoals ~10 km from shore, …


Aeolian Sand Stringers In The Upper Midwest, Usa: Morphology, Stratigraphy, And Paleoenvironmental Significance, Kenzie L. Shandonay 2021 Minnesota State University, Mankato

Aeolian Sand Stringers In The Upper Midwest, Usa: Morphology, Stratigraphy, And Paleoenvironmental Significance, Kenzie L. Shandonay

All Graduate Theses, Dissertations, and Other Capstone Projects

Sand stringers are subtle (~1-10 m high), elongate (several km long, up to 100 m wide) aeolian landforms that lack a slip face and generally have a northwest-southeast orientation. They are ubiquitous across the Upper Midwest, including southeast Minnesota and western Wisconsin. Despite their prevalence, the timing, processes, and environmental conditions during sand stringer formation and evolution are poorly understood. This research aims to describe sand stringer morphology and stratigraphy, reconstruct regional paleoclimate, and characterize the timing and geomorphic processes of sand stringer formation and evolution in response to shifts in environmental conditions. This study investigates two sand stringers: Good-1 …


New Hampshire Continental Shelf Geophysical Database: Vibracore Logs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. McAvoy, Maxlimer Coromoto Vallee-Anziani 2021 University of New Hampshire CCOM/JHC, Durham

New Hampshire Continental Shelf Geophysical Database: Vibracore Logs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: Vibracore Logs and Sediment Data" contains complete core logs and sediment grain size data from twenty‐three vibracores taken on the New Hampshire shelf in 1984 and 1988. During the present program, the original core descriptions, data, and photographs were verified and significantly expanded, synthesized, and presented in uniform core logs.The vibracore logs, sediment data, and the depositional environments are discussed in detail in Ward et al., 2021 (https://dx.doi.org/10.34051/p/2021.26).


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: Faculty and Staff Publications

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.


2021 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin 2021 University of Nebraska at Lincoln

2021 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin

Conservation and Survey Division: Faculty and Staff Publications

Seventeen participants completed the 2021 Water Leaders Academy bringing the total number of graduates to 153 since the inception of the program in 2011. Assessments of participants’ transformational leadership skills, champion of innovation skills, water knowledge, engagement with water issues, civic capacity, entrepreneurial leadership behaviors, and boundary spanner abilities showed significant increases over the course of the year, according to both the participants and their raters. Feedback from the participants was highly positive and constructive. Academy planners are addressing participant concerns. Only minor changes are planned for the 2022 Academy curriculum. Results of the program assessment indicate that the curriculum …


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