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Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour 2017 James Madison University

Characterizing Subsurface Void Spaces And Water Distribution And Flow Patterns In Cave Hill Karst Using Resistivity, Jacob A. Gochenour

Senior Honors Projects, 2010-2019

Describing the distribution of groundwater is essential in understanding the evolution of geomorphologic features in karst topography. Electrical resistivity allows us to find a model of subsurface distribution of resistivity that enables the visual recognition of groundwater and void spaces. The purpose of this research is to implement electrical resistivity to describe the spatial relationship of groundwater and karstic features at Grand Caverns National Natural Landmark, Grottoes, Virginia. Two locations of interest, a karstic swale and sinkhole area, were identified for the deployment of electrical resistivity. Both, dipole-dipole and Schlumberger arrays were collected for each deployment. A total of ten …


Evaluating Fault-Line Escarpment Exposure In The Guadalupe Mountains Of West Texas And New Mexico, Audrey Anne Happel 2017 Illinois State University

Evaluating Fault-Line Escarpment Exposure In The Guadalupe Mountains Of West Texas And New Mexico, Audrey Anne Happel

Theses and Dissertations

The Permian stratigraphy of the Guadalupe Mountains is well-known due to the impeccable exposure of Permian strata along distinct escarpments that define the boundaries of the range. Even though the Permian strata have been closely examined to understand the associated petroleum reservoirs in the adjacent Delaware basin, little work has been done on the escarpments that expose the well-known rocks at the surface by way of tectonic and erosional processes. The development of escarpments are directly affected by multiple processes that create the landscape, and can be used as a tool to temporally and spatially constrain tectonic and erosional activity …


Nutrient Variations Of Six Surface Water Bodies In Mchenry County, Il, Jacob Piske 2017 Augustana College, Rock Island Illinois

Nutrient Variations Of Six Surface Water Bodies In Mchenry County, Il, Jacob Piske

Celebration of Learning

This research analyzes water quality from several ponds in McHenry County, Illinois, with a goal of developing a understanding of pollution sources and temporal variations in concentrations of nitrate, potassium, phosphorus, chlorine, and sodium. Over the past 25 years, the population of McHenry County has grown rapidly, with residential developments expanding into former farmlands. Yet, the county remains heavily agricultural, with roughly 60% of the surface area used for agricultural purposes. Concentrations of NO3-, P+, K+, Cl-, and Na+ were analyzed from six sites: two in subdivisions, two in farmland, and two near major highways. Data were collected once a …


Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard 2017 Augustana College, Rock Island Illinois

Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard

Celebration of Learning

Ross Island Copper Mine, located in Killarney National Park, Killarney, Ireland, is known for archeological artifacts of copper from the Bronze Age. Copper production surged in the late 1700s and into the mid-1800s. The mine included both open pits (e.g. Blue Hole) and underground excavations (e.g. Western Mine). Copper veins were found in the Mississippian-aged limestone bedrock along with chalcopyrite and tennantite ore. In 1912, tourism had become the main source of income in the area, and the mines and the land surrounding them were remediated and became a part of the national park. Mine shafts were filled in, waste …


Dendrochronological Analysis Of Historical Structures In Southwestern Ohio Dewitt House Oxford, Ohio., 2017 The College of Wooster

Dendrochronological Analysis Of Historical Structures In Southwestern Ohio Dewitt House Oxford, Ohio.

Historic Structures

Dating historical structures in Oxford Ohio using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Fetters, Caitlin; Krivicich, Mike; Lehmann, Sophie; Wiles, Greg


A Floral Assemblage Of The Upper Cretaceous El Gallo Formation, El Rosario, Baja California, Mexico, Reilly F. Hayes, Marisol Montellano-Ballesteros, Gerardo Álvarez-Reyes, René Hernandez-Rivera, David E. Fastovsky 2017 Department of Geosciences, University of Rhode Island

A Floral Assemblage Of The Upper Cretaceous El Gallo Formation, El Rosario, Baja California, Mexico, Reilly F. Hayes, Marisol Montellano-Ballesteros, Gerardo Álvarez-Reyes, René Hernandez-Rivera, David E. Fastovsky

Senior Honors Projects

Over the past eight months, I have collaborated with paleontologists from the Universidad Nactional Autónoma de México to formally describe plant fossils they uncovered in Baja California between their 2013 and 2016 field seasons. We report the first floral assemblage of the dinosaur-aged El Gallo Formation, Baja California, Mexico, a small (82-specimen) collection of plant fossils from fossil soils contained within the 75.84 +/- 0.05 to 74.55 +/- 0.09 million-year-old El Disecado Member of the unit. A compound fruit belonging to the genus Operculifructus, previously reported from the 3.40 to 1.08 million year younger Cerro del Pueblo Formation, Coahuila, …


Lithology And Depositional Environments Of A Portion Of The Clays Ferry Formation (Middle And Upper Ordovician) Exposed At Silver Creek, Madison County, Kentucky, Autumn Murray 2017 Eastern Kentucky University

Lithology And Depositional Environments Of A Portion Of The Clays Ferry Formation (Middle And Upper Ordovician) Exposed At Silver Creek, Madison County, Kentucky, Autumn Murray

EKU Faculty and Staff Scholarship

We measure, describe, and interpret a carbonate stratigraphic section within the Clays Ferry Formation (Middle and Upper Ordovician) cropping out in Madison County, Kentucky (USGS Kirksville 7.5” quadrangle). The total thickness of the measured section is 4.76 m. We sampled the stratigraphic section at approximately half-meter intervals, also taking samples at lithology changes. We collected a total 20 samples, all of which were slabbed, and then selected 12 samples for thin section analysis.

Observed lithologies represent discrete depositional environments. The rocks are dominantly limestones with some carbonate shales deposited in shallow-water depositional environments that are generally open-marine, subtidal with perhaps …


Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi 2017 Clark University

Global Deforestation Prediction: Summer Internship At Clark Labs, Tianze Li, Yahsee Joshi

Sustainability and Social Justice

This paper is a description of our internship with Clark Labs in the summer of 2016. We worked as research assistants in the Deforestation Risk Prediction project for Ecosystem Services team. This goal of the project was to predict deforestation at global, continental and national level. Our responsibilities were to choose the variables that may influence the deforestation and to use Land Change Modeler in TerrSet to test the variables and create the deforestation prediction maps. We highly recommend this internship with Clark Labs to other GISDE students who are interested in land change analysis.


Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott 2017 Clark University

Geoscientists-In-The-Park Summer Internship Mapping Shoreline Change With The National Park Service, Michael P. Endicott

Sustainability and Social Justice

This project paper details the activities carried out as a Geologist/GIS Specialist in the Gateway National Recreation Area as a part of the Geoscientists-In-The-Park internship program. The focus of this position was on supporting the geomorphological monitoring efforts of the National Park Service. This was accomplished through a combination of field data collection, GIS analysis, report writing, and project work. By the end of the internship, substantial progress was made to the formation of Gateway’s Annual 1D and 2D report for 2015-2016, field data were collected for the 2016 summer season, changes in geomorphology were explored and summarized for the …


Magmatic Hydrothermal Alteration And Secondary Post-Shock Features In Martian Olivine-Phyric Basalt Northwest Africa 10416; Petrology And Geochemistry Of Primitive Achondrite Northwest Africa 11042, Zoltan Vaci 2017 University of New Mexico

Magmatic Hydrothermal Alteration And Secondary Post-Shock Features In Martian Olivine-Phyric Basalt Northwest Africa 10416; Petrology And Geochemistry Of Primitive Achondrite Northwest Africa 11042, Zoltan Vaci

Earth and Planetary Sciences ETDs

The Martian olivine-phyric basalt Northwest Africa (NWA) 10416 contains large olivine xenocrysts whose cores have been stained brown by hydrothermal alteration and whose rims are composed of pristine olivine overgrowths. Microanalysis of these olivine cores reveals various degrees of amorphization, some of which have been overprinted by terrestrial weathering, evident as part of a weathering rind along the exposed surface of the meteorite. Studies of a completely unweathered terrestrial analogue basalt from southern Colorado reveal similar features and indicate that both basalts were altered in a supersolidus magma chamber setting. The alteration features in NWA 10416 thus imply the presence …


Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz 2017 Missouri State University

Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz

Graduate Theses/Dissertations

The Proterozoic Midcontinent Rift System (MCRS) is considered one of the most important tectonic features in North America and was formed during a continental breakup event at 1.1 Ga (billion years). The MCRS is totally covered by Phanerozoic sedimentary rocks except in the Lake Superior region. Consequently, the geological characteristics of the MCRS are primarily inferred from extrapolations from the outcrop areas, drill holes, and from a variety of geophysical investigations. Iowa has a large segment of the MCRS which to date has only been partially investigated geophysically with little information regarding the lower crustal and upper mantle structure under …


Basement And Cover Structural Analysis Along The Eagle River Gorge, Sawatch Range, Colorado, Kaitlin Lee Askelson 2017 Stephen F Austin State University

Basement And Cover Structural Analysis Along The Eagle River Gorge, Sawatch Range, Colorado, Kaitlin Lee Askelson

Electronic Theses and Dissertations

The Sawatch Range within the Rocky Mountains of central Colorado exposes Paleoproterozoic basement and overlying Paleozoic sedimentary rocks with a complex history of ductile and brittle deformation.

The goal of this study is to conduct analyses of brittle structures that occur in the basement and cover units to determine geometric relationships between the structures, provide a detailed description of structures and refine a geologic history for structures along the basement-cover contact in the northeastern Sawatch Range along the Eagle River canyon and U.S. Highway 24 from Red Cliff to Gilman, Colorado. Paleoproterozoic basement rocks include the Cross Creek granite, diorites, …


Evidence For Distributed Clockwise Rotation Of The Crust In The Northwestern United States From Fault Geometries And Focal Mechanisms, Thomas M. Brocher, Ray E. Wells, Andrew P. Lamb, Craig S. Weaver 2017 U.S. Geological Survey, Menlo Park

Evidence For Distributed Clockwise Rotation Of The Crust In The Northwestern United States From Fault Geometries And Focal Mechanisms, Thomas M. Brocher, Ray E. Wells, Andrew P. Lamb, Craig S. Weaver

Geology Faculty Publications and Presentations

Paleomagnetic and GPS data indicate that Washington and Oregon have rotated clockwise for the past 16 Myr. Late Cenozoic and Quaternary fault geometries, seismicity lineaments, and focal mechanisms provide evidence that this rotation is accommodated by north directed thrusting and right-lateral strike-slip faulting in Washington, and SW to W directed normal faulting and right-lateral strike-slip faulting to the east. Several curvilinear NW to NNW trending high-angle strike-slip faults and seismicity lineaments in Washington and NW Oregon define a geologic pole (117.7°W, 47.9°N) of rotation relative to North America. Many faults and focal mechanisms throughout northwestern U.S. and southwestern British Columbia …


(Uranium-Thorium)/Helium Thermochronologic Constraints On Secondary Iron-Oxide Mineralization In Southwestern New Mexico, Michael Channer 2017 Utah State University

(Uranium-Thorium)/Helium Thermochronologic Constraints On Secondary Iron-Oxide Mineralization In Southwestern New Mexico, Michael Channer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Southwestern New Mexico experienced protracted volcanism from ~60 Ma to 500 ka and associated epithermal mineralization. We apply hematite (U-Th)/He (hematite He) thermochronology to fracture-hosted hematite in the Lordsburg Mining District to resolve the timing of mineralization related to hydrothermal fluid circulation. We interpret hematite He dates with integrated field and structural observations, scanning electron microscopy to characterize hematite texture and grain size distribution, and zircon U-Pb and zircon (U-Th)/He (zircon He) chronology to constrain the timing of host rock formation and the ambient low-temperature thermal history, respectively. Undeformed hematite fills fractures cut a brecciated rhyolite and preserve open voids. …


The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard 2017 University of Nebraska-Lincoln

The Groundwater Atlas Of Richardson County, Nebraska, Dana P. Divine, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Richardson County that has not been published in readily accessible formats previously. Many of the maps presented herein are based on data from registered well logs and test hole logs that are publicly available on-line, which become more valuable when compiled, analyzed, and discussed as a whole. The focus of the maps presented in this report is the accessibility of groundwater for pumping.


Environmental Changes Across The Early Mississippian Carbon Isotope Excursion, Dev Krishna Maharjan 2017 University of Nevada, Las Vegas

Environmental Changes Across The Early Mississippian Carbon Isotope Excursion, Dev Krishna Maharjan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Early Mississippian K–O (Kinderhookian-Osagean) δ13C excursion or TICE (mid-Tournaisian carbon isotope excursion) is characterized by an anomalous carbonate carbon isotope value of ≥5‰ that has been documented from numerous stratigraphic sections across the globe. This δ13C excursion coincides with global cooling and sea-level fall and predicts a significant change in seawater chemistry. However, sulfate sulfur isotope data across the K-O δ13C excursion reported in previous studies seem not to be responsive to the carbon cycle. Likewise, a recent study has documented a unidirectional increase in nitrogen isotopes across this excursion, which is not anticipated considering the amount of organic …


An Elemental Highway: Investigation Of A High Nickel Anomaly In Olivine From The Island Of Niihau, Hawaii, Alexander James Valentine 2017 University of Nevada, Las Vegas

An Elemental Highway: Investigation Of A High Nickel Anomaly In Olivine From The Island Of Niihau, Hawaii, Alexander James Valentine

UNLV Theses, Dissertations, Professional Papers, and Capstones

The study of volcanic geochemistry is one of the main gateways for investigating the Earth’s mantle. One important topic in the field is that of nickel (Ni) in the mineral olivine. While Ni is a compatible element in olivine, its high concentration at a given MgO content is not well understood. A variety of hypotheses have been proposed, including attributing presence of Ni to pyroxenite source melting, contribution from the core, or variation in peridotite source melting. In addition to the other hypotheses, chemical diffusion may also be a mechanism for enriching olivine Ni concentration. Magnesium-iron (Mg-Fe) isotopic measurements have …


Magmatic Evolution Of Early Subduction Zones: Geochemical Modeling And Chemical Stratigraphy Of Boninite And Fore Arc Basalt From The Bonin Fore Arc, Emily A. Haugen 2017 Utah State University

Magmatic Evolution Of Early Subduction Zones: Geochemical Modeling And Chemical Stratigraphy Of Boninite And Fore Arc Basalt From The Bonin Fore Arc, Emily A. Haugen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Izu-Bonin-Mariana arc stretches south from Japan to Guam in the Western Pacific. International Ocean Discovery Project Expedition 352 drilled four core in the fore arc of the Izu-Bonin arc east of the Bonin Islands: U1439C, U1440B, U1441A, and U1442A. From the four core, 124 samples were retrieved and analyzed for major and trace elements. Two main rock types were identified: FAB and boninite. FAB is a Mid-Ocean Ridge Basalt (MORB)-like tholeiite with variable fluid mobile element enrichment such as Rb, Ba, and Sr, and low Ti/V ratios more similar to an island arc volcanic than a mid-ocean ridge volcanic. …


Spatiotemporal Evolution Of Pleistocene And Late Oligocene-Early Miocene Deformation In The Mecca Hills, Southernmost San Andreas Fault Zone, Amy C. Moser 2017 Utah State University

Spatiotemporal Evolution Of Pleistocene And Late Oligocene-Early Miocene Deformation In The Mecca Hills, Southernmost San Andreas Fault Zone, Amy C. Moser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seismogenically active faults (those that produce earthquakes) are very complex systems that constantly change through time. When an earthquake occurs, the rocks surrounding a fault (the “fault rocks”) become altered or damaged. Studying these fault rocks directly can inform what processes operated in the fault and how the fault evolved in space and time. Examining these key aspects of faults helps us understand the earthquake hazards of active fault systems.

The Mecca Hills, southern California, consist of a set of hills adjacent to the southernmost San Andreas Fault. The topography is related to motion on the San Andreas fault, which …


Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey 2017 University of Arkansas, Fayetteville

Comparison Of Flow Dynamics And Bifurcation Angles In Tributary And Distributary Channel Networks, Thomas Coffey

Graduate Theses and Dissertations

The dynamics of channel mouth bifurcations on river deltas can be understood using theory developed in tributary channel networks. Bifurcations in groundwater-fed tributary networks have been shown to evolve dependent on diffusive ground water flow patterns

directly adjacent to the channel network, producing a critical angle of 72°. We test the hypothesis that bifurcation angles in distributary channel networks are likewise dictated by a diffusive external flow field, in this case the shallow surface water surrounding the subaqueous portion of distributary channels in a deltaic setting. We measured 25 unique distributary bifurcations in an experimental delta and 197 bifurcations in …


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