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Petrology Of An Oxidized Blueschist Cobble From The San Onofre Breccia, California, Usa, Alaina A. Helm 2021 Oberlin College

Petrology Of An Oxidized Blueschist Cobble From The San Onofre Breccia, California, Usa, Alaina A. Helm

Honors Papers

The mid-Miocene San Onofre Breccia (SOB) found along the southern California borderlands contains clasts of several lithologies including high-pressure metamorphic rocks commonly thought to be shed from the Catalina Schist. Sorensen concluded the San Onofre Schist was part of the Franciscan Complex, although at that time the Catalina subduction was considered to be part of the Franciscan Complex. In this study, a ~10 cm cobble collected from the San Onofre type locality was studied to describe its mineralogy and estimate its conditions of metamorphism. The cobble is composed of glaucophane (35%) + epidote (15%) + garnet (13%) + phengite (12%) …


Last Interglacial Climate From Dendostrea Frons Oysters, Verrill Island, Bermuda, Lillian Minnebo 2021 Grand Valley State University

Last Interglacial Climate From Dendostrea Frons Oysters, Verrill Island, Bermuda, Lillian Minnebo

Student Summer Scholars Manuscripts

The Bermuda Islands preserve carbonates recording many past changes in sea level, including multiple warm and cool geologic intervals. Several localities expose shell-rich deposits from the Last Interglacial (~125,000 years ago), a time broadly similar to climate today that can potentially serve as an analog for future conditions. Here, we use δ18O analyses of fossil mollusks to estimate past temperatures and seasonality and compare our data with those from other species.

Eight Dendostrea frons oysters were sampled along their growth axes to reconstruct seasonal temperature curves. We report a mean δ18O value of -0.51 ± 0.17‰, corresponding to a temperature …


Regional Correlation And Depositional History Using Well Log And Core Data Of The Middle Devonian Marcellus Poseidon 8m Well, Westmoreland County, Pennsylvania, Usa, Emily R. Jackson 2021 West Virginia University

Regional Correlation And Depositional History Using Well Log And Core Data Of The Middle Devonian Marcellus Poseidon 8m Well, Westmoreland County, Pennsylvania, Usa, Emily R. Jackson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Marcellus Shale is the largest natural gas producing formation in the Appalachian basin, and as such, presents a unique opportunity for continued research on an area that is critical to meeting the energy needs of the current society. Although the Marcellus has historically been extensively researched, acquisition of well log and core data from the Marcellus Poseidon 8M well in Westmoreland County, PA, allows for application of a new method of data integration, which was utilized in this project to specifically understand the depositional environment and create a correlation with other study wells throughout the basin. This integration was …


Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli 2021 West Virginia University

Application Of 3d Seismic Signal And Geomechanical Attributes For Subsurface Fracture Characterization: A Case Study In Clearfield County, Central Pennsylvania, Iman F. Zulkapeli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hydrocarbon exploration in unconventional reservoirs is highly risky due to the nature of the reservoirs and the variability in fractures and reservoir geomechanical properties in the subsurface. The reservoir needs to be fully characterized to avoid any complication such as frac hit, wellbore failure, blowout, or even a dry hole. The Clearfield reservoir produces an exceptionally low amount of gas, compared to the neighboring region in the proximity, which has been poorly understood. This raises the question as to what causes the reservoir to have low productivity.

This study focuses on the natural fracture characterization using high-quality 3D seismic signal …


Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras 2021 West Virginia University

Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras

Graduate Theses, Dissertations, and Problem Reports (ETD)

Red siliciclastics and evaporites of Permian Nippewalla Group in mid-continental US were deposited in western equatorial Pangea. Previous studies of these rocks record Permian air temperatures as high as 73 °C, saline lake waters with a pH as low as ~1, and sedimentology that shows arid conditions. This current study conducts detailed sedimentological observations and geochemical analyses of the Blaine Formation of the Nippewalla Group. The Rebecca K. Bounds core from west-central Kansas is used to interpret the depositional environments and diagenetic history of the Blaine Formation.

The lithologies of the Blaine Formation, listed in order of most to least …


Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. DeMott 2021 Central Washington University

Long-Term Geomorphic Effects Of The Glines Canyon Dam Removal On The Elwha River, Washington, Usa, Alyssa D. Demott

All Master's Theses

The Elwha River once provided vital habitat for a variety of salmonid species, but after two dams were emplaced on the river in the early 1900s, habitat diminished, and salmon populations declined. From 2011-2014, the dams were finally removed to restore the Elwha ecosystem. To understand the long-term geomorphic impacts of the Glines Canyon Dam removal on the Elwha River, I quantified changes in four parameters: in-channel large wood, main channel sinuosity, channel braiding, and sedimentation. High-resolution imagery from 2012-2020 was used to map large wood and digitize main and secondary river channels, and field surveys were completed at study …


Tsunami Deposits And Tsunami Modeling Of The 900 Ad Seattle Fault Event In Northern Puget Sound, Andrew A. Raulerson 2021 Central Washington University

Tsunami Deposits And Tsunami Modeling Of The 900 Ad Seattle Fault Event In Northern Puget Sound, Andrew A. Raulerson

All Master's Theses

Puget Sound has a history of earthquakes and tsunamis with an ever-expanding knowledge of these events. The focus of this study is the Seattle fault earthquake and resulting tsunami 1100 years ago. This study aimed at refining the extent of tsunami inundation north of the fault using a two-phased approach: a field study at Elger Bay and tsunami modeling. Tsunami deposits dating to this event have been observed in six sites total sites in Puget Sound, and four of them are in northern Puget Sound. At Elger Bay I found one tsunami deposit in cores from the southwest corner of …


Relationships Among Mineralogy, Geochemistry, And Oil And Gas Production In The Tuscaloosa Marine Shale, Hayley Roxana Beitel 2021 Missouri University of Science and Technology

Relationships Among Mineralogy, Geochemistry, And Oil And Gas Production In The Tuscaloosa Marine Shale, Hayley Roxana Beitel

Masters Theses

"The Tuscaloosa Marine Shale (TMS) is an unconventional shale reservoir located in southeast Louisiana and southwest Mississippi. Limited mineralogical and geochemical data for the TMS have been published. The data that do exist indicate that the formation is heterogeneous. Consequently, previous investigators and oil and gas companies have not managed to effectively link mineralogical and chemical changes to oil and gas production in the TMS. These linkages are critical to establish for future exploration efforts. In this study, we attempt to establish these relationships by gathering all existing mineralogical and chemical data in the TMS, including newly acquired data from …


Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer 2021 West Virginia University

Effect Of Oxidative Breakers On Organic Matter Degradation, Contaminant Mobility And Critical Mineral Release During Shale-Fracturing Fluid Interactions In The Marcellus Shale, Shaun Donmoyer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Production of oil and gas from organic-rich shale formations has become viable through advancements in multi-stage hydraulic fracturing. The decline of shale gas production after the initial days of fracturing operations coupled with falling oil and gas prices, has pushed industry operators to use new chemical additives as an attempt to increase hydrocarbon production. The implementation of highly reactive fracturing fluids that include strong oxidizing agents, pose as a potential solution to increase well productivity. Strong oxidizing chemicals commonly known in fracturing operations as breakers, are used to improve the viscosity of gel-based fluids after the proppant is transported into …


Multi-Scale Virtual Field Experience, Madeline S. Marshall, Melinda C. Higley 2021 Albion College

Multi-Scale Virtual Field Experience, Madeline S. Marshall, Melinda C. Higley

University Faculty Publications and Creative Works

Field experiences are a critical component of undergraduate geoscience education; however, traditional onsite field experiences are not always practical due to accessibility, and the popularity of alternative modes of learning in higher education is increasing. One way to support student access to field experiences is through virtual field trips, implemented either independently or in conjunction with in-person field trips. We created a virtual field trip (VFT) to Grand Ledge, a regionally important suite of sedimentary outcrops in central lower Michigan, USA. This VFT undertakes all stages of a field project, from question development and detailed observation through data collection to …


A Reference Section For The Otavi Group (Damara Supergroup) In Eastern Kaoko Zone Near Ongongo, Namibia, P.F. Hoffman, Sara B. Pruss, C.L. Blättler, E.J. Bellefroid, B.W. Johnson 2021 University of Victoria

A Reference Section For The Otavi Group (Damara Supergroup) In Eastern Kaoko Zone Near Ongongo, Namibia, P.F. Hoffman, Sara B. Pruss, C.L. Blättler, E.J. Bellefroid, B.W. Johnson

Geosciences: Faculty Publications

A reference section for the Otavi Group (Damara Supergroup) in the East Kaoko Zone near Ongongo is proposed and described. The section is easily accessible, well exposed, suitable for field excursions, and well documented in terms of carbonate lithofacies, depositional sequences and stableisotope chemostratigraphy. The late Tonian Ombombo Subgroup is 355 m thick above the basal Beesvlakte Formation, which is not included in the section due to poor outcrop and complex structure. The earlymiddle Cryogenian Abenab Subgroup is 636 m thick and the early Ediacaran Tsumeb Subgroup is 1020 m thick. While the section is complete in terms of formations …


The Effects Of Heterogeneities And Syn-Deformational Partial Melting On Rock Strength Evolution And Melt Migration, Nicole Wagner 2021 The University of Akron

The Effects Of Heterogeneities And Syn-Deformational Partial Melting On Rock Strength Evolution And Melt Migration, Nicole Wagner

Williams Honors College, Honors Research Projects

In nature, the segregation of granitic melts at the source may be controlled by fabric and compositional heterogeneities in the source rock, such as foliation and lineation. To investigate the influence of foliation/lineation orientation and composition on rock strength and melt interconnectivity, I performed a series of experiments on cores of a fine-grained gneiss (Gneiss Minuti) and a fine-grained muscovite-bearing quartzite (Moine Thrust quartzite). These rocks were cored at six primary orientations parallel, 45 degrees, and perpendicular to the foliation and lineation and were deformed at a constant temperature of 900°C, pressure of ~2 GPa, and strain rate of ~10-6/s …


Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw ms 2021 University of Montana

Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw Ms

Graduate Student Theses, Dissertations, & Professional Papers

Studying cordierite orthoamphibole gneisses (COG) from five different mountain ranges across the Montana Metasedimentary Terrane (MMT) of the Wyoming Province offers a unique opportunity to elucidate the enigmatic origins and petrogenesis of the lithology in addition to gaining a further understanding of Precambrian crustal assembly processes. Geochemical analyses suggest that COG originates from a basalt that underwent metasomatic alteration, likely via seawater, prior to metamorphism. Moreover, COG is considered to represent oceanic crust that was part of the epicontinental sea adjacent to the Wyoming Province before collision with the Medicine Hat Block. Field observations of associated lithologies such as marbles, …


Diagenesis Of The Lower Permian Wolfcamp Formation, West Texas: Implications For Reservoir Quality In The Midland Basin, Kory John Talcott 2021 The University Of Montana

Diagenesis Of The Lower Permian Wolfcamp Formation, West Texas: Implications For Reservoir Quality In The Midland Basin, Kory John Talcott

Graduate Student Theses, Dissertations, & Professional Papers

This study focuses on documenting the diagenesis and pore evolution within the lower Permian Wolfcamp B Formation in two producing wells from the Midland Basin of west Texas. Both wells are located near the northeastern margin of the Midland basin, with well A located proximal to the basin margin and well B located about 20km down depositional dip. The entire Wolfcamp B interval has been cored from both wells.

In both wells, the Wolfcamp B consists of calcareous and siliceous mudstone, skeletal wackestone, packstone, grainstone, rudstone, and floatstone facies that were deposited below wave base by a combination of suspension …


Glacial Deposits, Vol. 46, 2021, Department of Geography, Geology, and the Environment 2021 Illinois State University

Glacial Deposits, Vol. 46, 2021, Department Of Geography, Geology, And The Environment

Glacial Deposits

Newsletter of the Department of Geography, Geology, and the Environment


Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark 2021 University of Mississippi

Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark

Electronic Theses and Dissertations

Bauxite is a heavily-mined aluminum ore that forms through the relative depletion of silica to aluminum. In North Mississippi, bauxite occurring within the Upper Midway and Lower Wilcox groups has been the subject of study for over a century. Despite the abundance and duration of research, controversy surrounds the subjects of bauxite genesis and economic value. The last detailed study of North Mississippi bauxite was in the 1980’s, so the goal of this project is to apply newly available technologies and modern hypotheses on bauxite formation to refine and obtain new data. Fieldwork observations yielded pisoliths, horizonation, and possible rhizoliths, …


Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward 2021 The University of Akron

Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward

Williams Honors College, Honors Research Projects

Analyzing the strength of synthetic quartz is essential to understanding the strength of natural milky quartz, which likely controls the strength of Earth’s continental crust. Synthetic quartz is sometimes used for deformation experiments because it has a homogenous water distribution unlike natural milky quartz. The purpose of this study is to determine if annealing synthetic quartz at T = 600°C will convert the water in synthetic quartz to free water, like milky quartz, but with little water loss. Following two annealing experiments at Texas A&M University, I performed four annealing experiments to measure the water content of five synthetic quartz …


Recent Flooding Events On The Chagrin And Cuyahoga Rivers, Ohio, Kayley Martin 2021 The University of Akron

Recent Flooding Events On The Chagrin And Cuyahoga Rivers, Ohio, Kayley Martin

Williams Honors College, Honors Research Projects

From the 1910s through the 1980s, the number of intense daily precipitation events in the United States remained constant, however, since the 1980s there has been an increasing trend in intense single-day precipitation events (U.S Environmental Protection Agency, 2016). One outcome of intense precipitation events is river flooding, particularly in the upper Midwest region where floods have increased in magnitude and frequency (U.S Environmental Protection Agency, 2016). In this thesis project, recent flooding history on the Chagrin and Cuyahoga Rivers in Ohio was studied to expand on previous research that observed an abrupt increase in high magnitude flood events on …


It's More Than What You Know: Conceptual Understanding And Spatial Skill Impact Student Sequence Stratigraphic Interpretation Skill, Bailey Zo Kreager 2021 Northern Illinois University

It's More Than What You Know: Conceptual Understanding And Spatial Skill Impact Student Sequence Stratigraphic Interpretation Skill, Bailey Zo Kreager

Graduate Research Theses & Dissertations

Sequence stratigraphic interpretation and 3-D spatial and spatiotemporal skills are considered important for the petroleum industry. Despite the importance of sequence stratigraphic interpretations for student careers, students struggle to understand basic concepts such as eustasy, relative sea-level and base-level. However, little is known about the relationship between spatial skill and sequence stratigraphy or the impact of instruction on sequence stratigraphic diagrams. This study begins to fill this gap by testing 1) whether spatial skills predict success on a sequence stratigraphic interpretation task, 2) the impact of Wheeler diagram instruction on student sequence stratigraphic interpretation skill, and 3) the impact of …


Structural Analysis And Interpretation Of Deformation Along The Keweenaw Fault System West Of Lake Gratiot, Keweenaw County, Michigan, Sophie A. Mueller 2021 Michigan Technological University

Structural Analysis And Interpretation Of Deformation Along The Keweenaw Fault System West Of Lake Gratiot, Keweenaw County, Michigan, Sophie A. Mueller

Dissertations, Master's Theses and Master's Reports

The Keweenaw fault is perhaps the most significant fault associated with the Midcontinent Rift System of the north-central United States. The fault, parallel to the south edge of the rift, has been interpreted as a rift-bounding normal fault that was inverted by subsequent compressional events, thrusting copper-bearing Portage Lake Volcanics (~ 1.1 Ga) over younger Jacobsville Sandstone. Geologic maps and cross sections published in the 1950s by the U. S. Geological Survey depict the fault with a well-defined, single, sinuous trace that is locally associated with smaller branch faults. Cross-sections from that time generally show a simple listric stratal geometry …


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