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Areal Extent And Volumes Of The Dinner Creek Tuff Units, Eastern Oregon Based On Lithology, Bulk Rock Composition And Feldspar Mineralogy, Teresa Rae Hanna 2018 Portland State University

Areal Extent And Volumes Of The Dinner Creek Tuff Units, Eastern Oregon Based On Lithology, Bulk Rock Composition And Feldspar Mineralogy, Teresa Rae Hanna

Dissertations and Theses

The Dinner Creek Tuff erupted during a period of rhyolitic volcanism coeval to the flood volcanism associated with the Columbia River Basalt Group. The High Rock Caldera Complex, Lake Owyhee and McDermitt volcanic fields account for ~90% of the rhyolites erupted between 16.7-15.0 Ma. Situated at the northern end of the Lake Owyhee volcanic field, the Dinner Creek Tuff was originally mapped as a ~2,000 km2 single ignimbrite confined to the Malheur Gorge. Streck et al. (2015) correlated tuff outcrops previously mapped as generic Miocene welded tuff as well as local units such as the "Mascall" or "Pleasant Valley" …


T.D.A. Cockerell (1866–1948) Of The University Of Colorado: His Contributions To The Natural History Of The California Islands And The Establishment Of Channel Islands National Monument, Daniel R. Muhs 2018 U.S. Geological Survey

T.D.A. Cockerell (1866–1948) Of The University Of Colorado: His Contributions To The Natural History Of The California Islands And The Establishment Of Channel Islands National Monument, Daniel R. Muhs

United States Geological Survey: Staff Publications

Theodore Dru Alison Cockerell was a naturalist at the University of Colorado from 1904 to 1947 and studied botany, zoology, and paleontology in North and South America, Asia, Australia, Africa, and Europe. In the latter part of his career, he studied the California islands and published many papers on their natural history, 16 of them in four years (1937–1940). He made important contributions to the natural history of the islands in four distinct ways: entomology of the islands, including identification of a number of new species of bees; discovery of fossil marine invertebrate faunas and recognition that the zoogeography of …


Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall 2018 University of South Florida

Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall

USF Tampa Graduate Theses and Dissertations

Field learning is an important aspect of geoscience education to teach or reinforce concepts and skills, and the highly social experience of field work can improve learning outcomes, create networks to support future academic success, and promote a sense of belonging in the geosciences. However, field learning presents significant barriers to participation for students with physical disabilities. The introduction of digital data collection and communication devices into traditional field work settings has created new opportunities to expand access to field learning experiences such as remote collaboration; a method of undertaking field work through collaborative teamwork and the use of digital …


Microtextural Studies Of Feldspar In Ordinary Chondrites, Jonathan A. Lewis 2018 University of New Mexico

Microtextural Studies Of Feldspar In Ordinary Chondrites, Jonathan A. Lewis

Earth and Planetary Sciences ETDs

Ordinary chondrites contain an important record of events that took place during the earliest period of solar system evolution. These include primary processes, such as chondrule formation, and secondary processes, those that affected asteroids after accretion and modified primary components. Secondary processes include aqueous alteration, thermal metamorphism, and shock effects from impact events. Secondary minerals can provide insight into the chemical and physical conditions that affected their parent asteroids. Feldspar is known to be a secondary mineral that crystallized during thermal metamorphism. The goal of this work is to use the formation and evolution of feldspar to elucidate the conditions …


Modeling Climate Change Impacts On Water Balance Components Of The Mackinaw River Watershed, Central Illinois, Joseph Honings 2018 Illinois State University

Modeling Climate Change Impacts On Water Balance Components Of The Mackinaw River Watershed, Central Illinois, Joseph Honings

Theses and Dissertations

Understanding the response of water cycle dynamics to climate change and human activity is essential for best management of water resources. This study used the USDA Soil-Water Assessment Tool (SWAT) to measure and predict major water balance variables including stream discharge, potential aquifer recharge, and surface storage in a small-scale watershed (~2,930 km²) in Central Illinois. The watershed is predominantly tile-drained agricultural land, which controls the nutrient dynamics and hydrology. Two reservoirs, Evergreen Lake and Lake Bloomington, and the Mahomet Aquifer in the watershed are used for public water supply. The subject watershed has been very sensitive to recent droughts, …


Regional Stress Regime Study Of East Texas Based On Orientation Of Fractures In The Weches Formation, Cory D. Ellison 2018 Stephen F Austin State University

Regional Stress Regime Study Of East Texas Based On Orientation Of Fractures In The Weches Formation, Cory D. Ellison

Electronic Theses and Dissertations

Fractures in the Weches Formation in a roughly 50 mile radius around Nacogdoches, Texas were documented and analyzed using data obtained at various outcrops. This data was used to infer information about the regional stress regime based on the direction of maximum/minimum horizontal stresses (SHmax / SHmin) that formed the fractures. This is based on the principle that systematic, steeply dipping, mode I joints propagate in the direction of SHmax and normal to the direction of SHmin. Joints in the Weches Formation are typically iron filled and are predominantly opening mode, indicated by crack-seal formation, steep dip (700 – 900) …


Twinning Strains In Synfolding Calcite, Proterozoic Sinian System, China, John P. Craddock, Junlai Liu, YuanYuan Zheng 2018 Macalester College

Twinning Strains In Synfolding Calcite, Proterozoic Sinian System, China, John P. Craddock, Junlai Liu, Yuanyuan Zheng

Faculty Publications

Synfolding calcite was precipitated between layers of Neoproterozoic sandy dolomite and striated parallel to the fold axis of an open anticline with a shallow plunge during folding. The fold had limb dips of 45° and plunged 20° to the south. The synfolding calcite had sub-horizontal grooves that trended parallel to the fold. Limb-hinge-limb calcite samples (3 samples; n = 100 grains) preserved a layer-parallel shortening strain that trended at an acute (45°) angle to the trend of the fold axis and fold lineations. Extension axes were vertical and there was no strain overprint (low NEVs). Shortening strain magnitudes were −2.9% …


Mapping Bedrock Topography Of The Portage And Schoolcraft Nw 7.5’ Quadrangles, Kalamazoo Co. Mi, Using The Hvsr Passive Seismic Method, Benjamin B. Seiderman 2018 Western Michigan University

Mapping Bedrock Topography Of The Portage And Schoolcraft Nw 7.5’ Quadrangles, Kalamazoo Co. Mi, Using The Hvsr Passive Seismic Method, Benjamin B. Seiderman

Masters Theses

This study utilizes the Horizontal to Vertical Spectral Ratio (HVSR) technique to map bedrock topography in the Portage and Schoolcraft NW quadrangles, Kalamazoo Co., MI, looking for buried bedrock valleys. Glacial sediment-landform assemblages dominate the study area, due to multiple advances of the Laurentide Ice Sheet (LIS). Tunnel valleys, which are one type of buried valley, are eroded by subglacial meltwater and commonly filled with the coarser varieties of glacial outwash, making them potential aquifers. The HVSR technique measures the ratio of horizontal to vertical ground motion, excited by ambient seismic noise, resulting in a peak at the resonance frequency. …


Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell 2018 Montana Tech

Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell

Graduate Theses & Non-Theses

Digital photogrammetry is becoming a more common method used for mapping geological and structural rock mass features in underground mining. The issue of capturing geological and structural data in inaccessible, unsupported areas of mines remains even when utilizing terrestrial photogrammetric methods; thus, geotechnical models of mines are left with incomplete datasets. Large unsupported underground voids, like stopes, have the potential to cause major failures, but by filling in the geotechnical data gaps in inaccessible areas, potential failures can be predicted through kinematic analysis of the area’s mapped discontinuities. Implementation of Unmanned Aerial Vehicles (UAVs) in underground mines and recent advances …


Geochemical And Petrological Investigation Of The Prospective Ni-Cu-Pge Mineralization At The Echo Lake Intrusion In The Upper Peninsula Of Michigan, Usa, Alexander J. Koerber 2018 Western Michigan University

Geochemical And Petrological Investigation Of The Prospective Ni-Cu-Pge Mineralization At The Echo Lake Intrusion In The Upper Peninsula Of Michigan, Usa, Alexander J. Koerber

Masters Theses

The Echo Lake Intrusion is located in Houghton and Ontonagon counties in the Upper Peninsula (UP) of Michigan. The intrusion is approximately 200 m below the surface and covers approximately 18 km2 in lateral extent. It is associated with the magmatic activities of a 1.1 Ga geologic event called the Midcontinent Rift. The rift is responsible for the formation of Ni-Cu ± PGE deposits in the Lake Superior Region. Based on its association with the Midcontinent Rift and a Cu and PGE enriched layer, the Echo Lake intrusion is identified as a prospect for an economic magmatic sulfide deposit.

The …


Geologic Mapping Of The Bronson North And Bronson South 7.5-Minute Quadrangles, Branch County, Michigan, Karl John Backhaus 2018 Western Michigan University

Geologic Mapping Of The Bronson North And Bronson South 7.5-Minute Quadrangles, Branch County, Michigan, Karl John Backhaus

Masters Theses

This study contributes to a better understanding of the glacial history of southwest Michigan through detailed surficial geologic and bedrock topography mapping within the Bronson North and Bronson South Quadrangles in Branch County, Michigan. This project was supported during the summer of 2017 by the USGS EDMAP program in conjunction with the Michigan Geological Survey. Hand-auger borings, grain size analysis tests, passive seismic depth-to-bedrock measurements, and ground penetrating radar transects were collected for this study. There are 350 feet of bedrock relief from west to east across the quadrangles, including a bedrock cuesta of Mississippian Coldwater Shale. This cuesta underlies …


Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek 2018 University of Exeter

Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek

Department of Earth, Environment and Sustainability Faculty Publications

Despite recent research identifying a clear anthropogenic impact on glacier recession, the effect of recent climate change on glacier-related hazards is at present unclear. Here we present the first global spatio-temporal assessment of glacial lake outburst floods (GLOFs) focusing explicitly on lake drainage following moraine dam failure. These floods occur as mountain glaciers recede and downwaste. GLOFs can have an enormous impact on downstream communities and infrastructure. Our assessment of GLOFs associated with the rapid drainage of moraine-dammed lakes provides insights into the historical trends of GLOFs and their distributions under current and future global climate change. We observe a …


Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. VanderMeer 2018 Western Michigan University

Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. Vandermeer

Dissertations

Pictured Rocks National Lakeshore is among the most popular parks in Michigan, yet prior to this study, it was the only National Park that lacked a detailed surficial geology map characterizing the distribution of sediments and landforms. Additionally, much of the landscape remained unexplored. These factors prevented thorough interpretations of landscape development and evolution. This research aims to map and further explore the relationship of glacial sediments and landforms throughout Pictured Rocks to refine and expand the current understanding of glacial events that shaped this landscape.

A new, detailed (1:24,000-scale) surficial geology map of the ten 7.5-minute quadrangles that contain …


Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel 2018 University of Dayton

Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel

Honors Theses

The Geological Time Scale is a fundamental tool for geoscientists that is revised and republished every eight years. It is a representation of the geologic record - a system composed of radioisotope dates interpolated into fossil successions that can be used to correlate rocks. The current Geologic Time Scale for the Ordovician Period (GTS 2012) is composed of a sequence of species ranges from a group of fossils called graptolites with interpolated radiometric dates. Building a global geologic time scale requires correlating between different biofacies.

In this thesis I will attempt to combine stratigraphic range data from different kinds of …


Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter 2018 Brigham Young University

Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter

Theses and Dissertations

THE PARADOX Basin is a northwest-southeast trending intracratonic basin that formedin southwestern Colorado, southeastern Utah and adjacent parts of Arizona and New Mexicoduring the late Paleozoic Era. During rise of the adjacent Uncompahgre Uplift (Ancestral RockyMountains) the rapidly subsiding basin was filled with over 2000 m of Permo-Pennsylvaniansediments. Stacked depositional sequences accumulated in three roughly parallel facies belts: anortheastern clastic belt (adjacent to uplift), a central salt and black shale belt, and asouthwestern carbonate belt. Over 400 million barrels of oil have been extracted from upperParadox (Desert Creek and Ismay) carbonates in the southern Blanding Subbasin (Greater AnethField) since 1956. …


Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher 2018 Old Dominion University

Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have been found to influence its cycling and longevity in the environment. Dissolution via leaching may be the main control on loss processes such as microbial or abiotic oxidation, mineral sorption, or export to aquatic systems. Yet, little is known about the controls on pyrogenic dissolved organic matter (pyDOM) generation or composition. Here, the yield and composition of pyDOM generated through batch leaching of a thermal series of oak and grass biochars, as well as several non-pyrogenic reference materials, was compared …


A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup 2018 Brigham Young University

A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup

Theses and Dissertations

Collections of straight, RADAR-bright, linear features, or BLFs, on Saturn's moon Titan are revealed in Cassini SAR (Synthetic Aperture RADAR) images. Most are widely distributed across the northern midlatitudes SAR on SAR swaths T18, T23, T30, T64, and T83 and in swath T56 in the southern midlatitudes. To understand the origin of these features, we compare them with terrestrial yardangs in Dunhuang, China, the Altiplano/Puna of Argentina, and the Lut Desert of Iran and with a similar morphological landform, linear dunes in the Namib Sand Sea, Namibia and on Titan. We apply a statistical classification model developed through random forests, …


A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith 2018 Brigham Young University

A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith

Theses and Dissertations

Pilot Valley, located in the eastern Basin and Range, north of Wendover, UT, contains numerous shorelines and depositional remnants of late Pleistocene Lake Bonneville. These remnants present classic ground penetrating radar (GPR) targets due to their coherent stratification, low clay, low salinity, and low moisture content. Three-dimensional (3D) GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters. While lake levels fluctuated due to flooding events, climatic changes were the dominant factor in controlling lake levels. In Pilot Valley, the paleowind entered from the northwest, with storms coming from the south, and circulated clockwise around the …


Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee 2018 Missouri University of Science and Technology

Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Pyrite is a common mineral with a higher density than most other minerals in the Eagle Ford Shale formation. Hence, if pyrite is not considered in the total organic carbon (TOC) estimation, based on density logs, it may lead to errors. In order to improve the accuracy of the TOC estimation, we propose an updated TOC estimation method that incorporates the concentration of pyrite and organic porosity. More than 15 m of Eagle Ford Shale samples were analyzed using Rock-Eval pyrolysis, X-ray fluorescence (XRF), and X-ray diffraction (XRD). TOC, elemental concentration, and mineralogical data were analyzed for a better understanding …


Craters Of The Moon National Monument Basalts As Unshocked Compositional And Weathering Analogs For Martian Rocks And Meteorites, Christopher T. Adcock, Arya Udry, Elisabeth M. Hausrath, Oliver Tschauner 2018 University of Nevada, Las Vegas

Craters Of The Moon National Monument Basalts As Unshocked Compositional And Weathering Analogs For Martian Rocks And Meteorites, Christopher T. Adcock, Arya Udry, Elisabeth M. Hausrath, Oliver Tschauner

Geoscience Faculty Research

The availability of terrestrial sites that are martian analogs allows researchers to investigate Mars using knowledge gained on Earth. Among the terrestrial analog sites for Mars is Craters of the Moon National Monument (COTM) in Idaho, U.S.A. Craters of the Moon National Monument is home to over 60 basalt lava flows, many of which have been dated from 2050 to 18 340 years before present (y.b.p.). Following previous authors, we examined the chemistry and petrogenesis of COTM basalts compared to basaltic martian rocks, martian meteorites, and meteorite clasts, and then examined the results of chemical weathering of the basaltic flows. …


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