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Evidence For Distal Bolide Impact And Tsunami Deposits In The Upper Atlantic Coastal Plain Of Moore County (North Carolina, Usa) Generated By The Eocene Chesapeake Bay Bolide Impact, G. Robert Ganis, Ralph H. Willoughby, David J. Cicimurri, G. Richard Whittecar, Steven J. Hageman May 2025

Evidence For Distal Bolide Impact And Tsunami Deposits In The Upper Atlantic Coastal Plain Of Moore County (North Carolina, Usa) Generated By The Eocene Chesapeake Bay Bolide Impact, G. Robert Ganis, Ralph H. Willoughby, David J. Cicimurri, G. Richard Whittecar, Steven J. Hageman

OES Faculty Publications

Beds interpreted as Eocene bolide-generated impact and tsunami deposits occur at Paint Hill in the Upper Atlantic Coastal Plain of Moore County, North Carolina, USA. These strata, herein named the Mount Helicon Formation, consist of four distinct beds comprising about one meter of total section. Bed 1 (the basal bed) is approximately 43 cm thick and consists of sandy carbonaceous clay with carbon glass and rock fragments and contains 14-18 parts per billion (ppb) iridium (interpreted as bolide impact ejecta). Bed 2 is approximately 9 cm thick and consists of non-cohesive silt-size particles and loosely bound sand-size accretionary lapilli-like masses …


Unraveling The Causal Influences Of Drought And Crop Production On Groundwater Levels Across The Contiguous United States, Nitin K. Singh, Sheila M. Saia, Ruchi Bhattacharya, Hoori Ajami, David M. Borrok May 2025

Unraveling The Causal Influences Of Drought And Crop Production On Groundwater Levels Across The Contiguous United States, Nitin K. Singh, Sheila M. Saia, Ruchi Bhattacharya, Hoori Ajami, David M. Borrok

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Groundwater depletion in agricultural-dominated regions is attributed to climate and irrigation withdrawals that support crop production. However, despite decades of effort, knowledge gaps remain in understanding the relative influence of drought and crop production on groundwater levels at the continental scale. Here, utilizing empirical observations, we simultaneously track how long-term trajectories of groundwater levels, crop production of seven crops, and drought have evolved over time, and then integrate these observations with a causality-based attribution framework to unravel the relative impact of drought and crop production on groundwater levels across the contiguous United States (CONUS). We find a dominant pattern of …


Comprehensive Global Data Set Of Uniformly Processed Shear-Wave Splitting Measurements, Jonathan Wolf, Thorsten W. Becker, Edward Garnero, Kelly H. Liu, John D. West May 2025

Comprehensive Global Data Set Of Uniformly Processed Shear-Wave Splitting Measurements, Jonathan Wolf, Thorsten W. Becker, Edward Garnero, Kelly H. Liu, John D. West

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Seismic anisotropy can inform us about convective flow in the mantle. Shear waves traveling through azimuthally anisotropic regions split into fast and slow pulses, and measuring the resulting shear-wave splitting provides some of the most direct insights into Earth's interior dynamics. Shear-wave splitting is a constraint for path-averaged azimuthal anisotropy and is often studied regionally. Global compilations of these measurements also exist. Such compilations include measurements obtained using different data processing methodologies (e.g., filtering), which do not necessarily yield identical results, and reproducing a number of studies can be challenging given that not all provide the required information, for example, …


Older Groundwater Reservoirs In Nebraska, Marvin P. Carlson, Steven S. Sibray Apr 2025

Older Groundwater Reservoirs In Nebraska, Marvin P. Carlson, Steven S. Sibray

Conservation and Survey Division: Faculty and Staff Publications

Sedimentary rocks below Nebraska's regional water table are saturated down to the crystalline igneous and metamorphic rocks of Precambrian age. The total thickness of these sedimentary rocks ranges from about 600 feet to over 10,000 feet. Nearly all current wells in Nebraska produce water from the near-surface, unconsolidated or partly consolidated rocks. Most studies to date -- interpretive reports, test drilling, inventory of wells, monitoring water levels, and water quality determinations -- have concentrated on these near-surface sources of groundwater.


Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai Apr 2025

Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai

Theses and Dissertations

The southern Appalachian mountain belt is an accretionary orogen that formed in the southeastern United States through several phases of oceanic subduction and continental collision during the Paleozoic Era and culminated in the formation of the supercontinent Pangaea. Although many U-Pb zircon ages have been collected from the igneous, metaigneous and metasedimentary rocks in the crystalline core of the southern Appalachians, there remain opportunities to better reconstruct the metamorphic and magmatic history of the southern Appalachians through the lens of zircon geochronology. Such data are valuable in identifying genetic relationships between candidate terranes of the orogen. Herein, I present laser-ablation …


Method For Low-Cost In Situ Measurement Of Dissolved Total Volatile Organic Compound Concentrations In Surface Waters, Teagan A. Jones Apr 2025

Method For Low-Cost In Situ Measurement Of Dissolved Total Volatile Organic Compound Concentrations In Surface Waters, Teagan A. Jones

ATU Scholars Symposium

Increases in volatile organic compounds (VOC) in developing areas poses risks to aquatic health. Water quality changes in surface waters, if measured, are often only for field parameters of pH, specific conductance, water temperature, and major ions, e.g. Ca2+, Mg2+, Na, Cl. Elevated VOC concentrations can negatively impact aquatic ecosystems even at low concentrations, but do not cause changes in commonly measured parameters and may go undetected based on monitoring these common parameters. Traditional sampling and benchtop analysis for VOC can be both time and cost prohibitive. Here we demonstrate the use of a low-cost in situ dissolved total VOC …


The Effects Of Climate Change On The Advancement Of West Nile Virus, Mackenzie R. Epperson Apr 2025

The Effects Of Climate Change On The Advancement Of West Nile Virus, Mackenzie R. Epperson

ATU Scholars Symposium

The West Nile virus (WNV) first emerged in the United States in the year 1999 within the state of New York and has become endemic throughout the country over time. This virus is contracted from an avian species acting as the reservoir host, by the vector species which are mosquitoes. From this point, the mosquitoes transmit the virus to humans and other mammals, which are the dead end hosts. The WNV often presents itself as flu-like symptoms, but in serious cases can cause severe arboviral neurological disease. Since this is an arbovirus, it is important to have the ability to …


The Geologic History Of The Chehalis Forearc Basin, Washington State, Usa, Rud Lamb Moe Apr 2025

The Geologic History Of The Chehalis Forearc Basin, Washington State, Usa, Rud Lamb Moe

Dissertations and Theses

The Chehalis Basin, in southwest Washington, is one of a series of forearc basins between the Cascade Arc and the Coast Range in the Pacific Northwest. While the Seattle basin to the north, and the Portland-Tualatin basins to the south are both relatively well studied, the geologic evolution of basins in between is poorly constrained. The Chehalis basin is underlain by accreted Eocene oceanic basalt of the Crescent Formation. The basin fill consists of sedimentary rocks and volcanic rocks deposited throughout the Cenozoic. It has undergone N-S shortening driven by transpressional stress from oblique subduction of the Juan de Fuca …


Estimated Amounts Of Terrestrial Carbon Mobilized And Sequestered By The 1980 Mount St. Helens Eruption, Washington State, Usa, Lizzet G. Reyes Apr 2025

Estimated Amounts Of Terrestrial Carbon Mobilized And Sequestered By The 1980 Mount St. Helens Eruption, Washington State, Usa, Lizzet G. Reyes

Dissertations and Theses

Volcanic eruptions significantly influence the geologic carbon cycle by emitting CO2 and mobilizing terrestrial carbon pools. The 1980 Mount St. Helens (MSH) eruption offers a unique case study, triggering a massive landslide that displaced 2.7 km3 of sediment, buried 600 km2 of forest, and disrupted regional carbon dynamics. Pre-eruption terrestrial carbon stocks, including aboveground biomass (AGB), dead biomass (D), and soil organic carbon (S), averaged 209.5 tC/ha. Post-eruption, total carbon density fell to 118.7 tC/ha, driven mainly by a 51% reduction in AGB, modest declines in D, and redistribution of S. Over 36 years, ecosystem recovery increased …


Experimental Impacts Into Sloped Targets, J.L.B. Anderson, Tyler S.L. Kadrie, A.L. Miller, C.J. Cline Ii Apr 2025

Experimental Impacts Into Sloped Targets, J.L.B. Anderson, Tyler S.L. Kadrie, A.L. Miller, C.J. Cline Ii

Research & Creative Achievement Day

Asymmetric craters have been ob-served on sloped surfaces on the Moon [1] and extensively across Vesta [2] and Ceres [3]. For example, Lowell Crater (Fig. 1A) is a large crater on the surface of the Moon that has a small-er crater, Lowell H, which formed when an asteroid impacted the sloped surface of Lowell’s crater rim [1]. The topography map of Lowell H (Fig. 1B) shows the original sloped crater wall, the highly asymmetric and slumped Lowell H crater, and the debris flows that formed during its collapse.

Typically, impact cratering experiments are performed into smooth, flat-lying targets as a …


Mgrre_Geolog_Collections Weber, Harry B 1 21011286290000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Weber, Harry B 1 21011286290000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Crowley, Orville 1 21037290830000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Crowley, Orville 1 21037290830000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Lopez, Byrdie Et Al 1 21015284730000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Lopez, Byrdie Et Al 1 21015284730000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Brown, Chloey 1 21049283400000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Brown, Chloey 1 21049283400000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Buell, Darius & Charlotte, & Wallrich, W&R 1 21009292220000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Buell, Darius & Charlotte, & Wallrich, W&R 1 21009292220000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Brokoff, Edmund & Coral 2 21051286160000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Brokoff, Edmund & Coral 2 21051286160000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Squires 1-11 21045296250000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Squires 1-11 21045296250000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Schultz, Emil 1 21051285590000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Schultz, Emil 1 21051285590000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Smith, George C 1 21007285830000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Smith, George C 1 21007285830000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections White, Irvine & Francis L 1 21051288350000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections White, Irvine & Francis L 1 21051288350000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Shea, Mortimer J Et Al 1-25 21035305630000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Shea, Mortimer J Et Al 1-25 21035305630000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Pavlis, Elmer & Dorothy 1-3 21055333270000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Pavlis, Elmer & Dorothy 1-3 21055333270000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Brokoff, Edmund & Coral 1 21051285580000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Brokoff, Edmund & Coral 1 21051285580000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Valleau Et Al 1-14 21055368810000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Valleau Et Al 1-14 21055368810000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections State Paradise 2-19 21055307630000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections State Paradise 2-19 21055307630000, Mgrre Western Michigan University

Geolographs

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Mgrre_Geolog_Collections Ramsay, Ferris Et Al 1-29 21055303130000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Ramsay, Ferris Et Al 1-29 21055303130000, Mgrre Western Michigan University

Geolographs

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Mgrre_Geolog_Collections State Union & Rokos Unit 1-18 21055314760000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections State Union & Rokos Unit 1-18 21055314760000, Mgrre Western Michigan University

Geolographs

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Mgrre_Geolog_Collections Wheeler State 1-21 21055319440000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Wheeler State 1-21 21055319440000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Weidenfeller 1-33 21055313560000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Weidenfeller 1-33 21055313560000, Mgrre Western Michigan University

Geolographs

No abstract provided.


Mgrre_Geolog_Collections Wise, Robert L & Dorothy 1-16 21055307510000, Mgrre Western Michigan University Apr 2025

Mgrre_Geolog_Collections Wise, Robert L & Dorothy 1-16 21055307510000, Mgrre Western Michigan University

Geolographs

No abstract provided.