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Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey 2016 California Polytechnic State University, San Luis Obispo

Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey

Natural Resources Management and Environmental Sciences

The Sierra Nevada batholith represents an archetypal continental arc, although the style of deformation throughout the history of the arc is only poorly understood, in part due to the voluminous nature of Late Cretaceous magmatism that has overprinted earlier structures. The purpose of this study is to gain a better understanding of pre-Late Cretaceous deformation in the Sierra Nevada batholith through a structural and geochronological study of the Jurassic White Fork pluton. A Jurassic age for the White Fork pluton is indicated by its inclusion of numerous 148 Ma Independence dikes, and geochronology on the White Fork pluton is limited …


Quartz Crystal Preferred Orientation And Recrystallization Patterns From Naturally Deformed Rocks Under Constriction, Riley Quine 2016 California Polytechnic State University, San Luis Obispo

Quartz Crystal Preferred Orientation And Recrystallization Patterns From Naturally Deformed Rocks Under Constriction, Riley Quine

Materials Engineering

This study analyzes crystal preferred orientation (CPO) patterns within constrictional quartz-rich gneisses. Quartz deformation and CPO patterns are an area of interest because quartz is one of the most prevalent minerals in earth's crust. Understanding the typical way that quartz crystals reorient under different states of strain can provide geologists with an additional tool for understanding paleo-strain. Temperature and strain geometry are two dominant factors that control the orientation of quartz crystals within a rock. Temperature determines which slip planes are active and slip planes typically reorient so that they are perpendicular to maximum stress. Previous workers have suggested that …


Contrasting Sediment Melt And Fluid Signatures For Magma Components In The Aeolian Arc: Implications For Numerical Modeling Of Subduction Systems, Denis Zamboni, Esteban Gazel, Jeffrey G. Ryan, Claudia Cannatelli, Federico Lucchi, Zachary D. Atlas, Jarek Trela, Sarah E. Mazza, Benedetto De Vivo 2016 Virginia Polytechnic Institute and State University

Contrasting Sediment Melt And Fluid Signatures For Magma Components In The Aeolian Arc: Implications For Numerical Modeling Of Subduction Systems, Denis Zamboni, Esteban Gazel, Jeffrey G. Ryan, Claudia Cannatelli, Federico Lucchi, Zachary D. Atlas, Jarek Trela, Sarah E. Mazza, Benedetto De Vivo

Geosciences: Faculty Publications

The complex geodynamic evolution of Aeolian Arc in the southern Tyrrhenian Sea resulted in melts with some of the most pronounced along the arc geochemical variation in incompatible trace elements and radiogenic isotopes worldwide, likely reflecting variations in arc magma source components. Here we elucidate the effects of subducted components on magma sources along different sections of the Aeolian Arc by evaluating systematics of elements depleted in the upper mantle but enriched in the subducting slab, focusing on a new set of B, Be, As, and Li measurements. Based on our new results, we suggest that both hydrous fluids and …


Shear Wave Splitting Analyses In Tian Shan: Geodynamic Implications Of Complex Seismic Anisotropy, Solomon G. Cherie, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Fansheng Kong, Cory A. Reed, Bin B. Yang 2016 Missouri University of Science and Technology

Shear Wave Splitting Analyses In Tian Shan: Geodynamic Implications Of Complex Seismic Anisotropy, Solomon G. Cherie, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Fansheng Kong, Cory A. Reed, Bin B. Yang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Tian Shan is a tectonically complex intracontinental orogenic belt situated between the Tarim Basin and the Kazakh Shield. The vast majority of the previous shear wave splitting (SWS) measurements were presented as station averages, which are only valid when the anisotropy structure can be approximated by a single layer of anisotropy with a horizontal axis of symmetry, i.e., a model of simple anisotropy. A variety of anisotropy-forming hypotheses have been proposed based on the station-averaged measurements. In this study, we measure the splitting parameters at 25 stations that recorded high-quality data from a wide back azimuthal range for the …


The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson 2016 Loma Linda University

The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure of carbonate rocks within the uplifted mountains of southwestern Utah presents a unique opportunity to study the growth, morphology and ecology of two upper Cambrian microbialite reefs located within the Hellnmaria Member of the Notch Peak Formation. The first reef contains meter-length, strongly elongate microbialites that grew in a deep, subtidal marine environment. These elongate microbialites formed as a result of coalescence of round ‘algal’ heads, a process known to produce compound microbialite structures in shallow water, but seldom explored as a key factor in the elongation of deep, subtidal forms that grew in ancient environments. The second reef …


The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu 2016 University of Nebraska-Lincoln

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Department of Earth and Atmospheric Sciences: Faculty Publications

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover …


Designing An Instructional Publication On The Geology Of Capitol Reef National Park, Kinsey Gayle Spiel 2016 Brigham Young University

Designing An Instructional Publication On The Geology Of Capitol Reef National Park, Kinsey Gayle Spiel

Theses and Dissertations

The wide variety of strata, structural features, and landscapes of Capitol Reef National Park result from its complex, yet discoverable history. Our task was to write and design an informative book on this complexity while making it engaging for the public. We approached the design of this book using Stufflebeam's (2007) CIPP model. The CIPP model uses both summative and formative evaluations in the categories of context, input, process, and product. It provides the framework to methodically investigate the value of a product and identify and correct less effective pedagogical and design elements during its development. We demonstrated the use …


Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy 2016 CUNY City College

Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy

Publications and Research

The two largest lakes on the Caribbean Island of Hispaniola, Lake Azuei in Haiti and Lake Enriquillo in the Dominican Republic, have experienced dramatic growth and surface area expansion over the past few years leading to severe flooding and loss of arable land around the lake perimeters. In order to better understand the reasons for this unprecedented rate of expansion and the resulting consequences a multi-disciplinary team comprised of researchers from Haiti, the DR, and the US have embarked on an extensive data collecting and hydrologic and climatological modeling campaign. While the sensor deployment entails stations that measure climatological data …


Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati 2016 Loma Linda University

Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati

Loma Linda University Electronic Theses, Dissertations & Projects

The Neoproterozoic Kingston Peak Formation (KPF) is known for its diamictites interpreted as of glacial origin. The KPF overlies the Beck Spring Dolomite (BSD) that contains microfossils and microbialites. This study aims to test correlation between outcrops and understand the abrupt change from BSD to KPF. It focuses on the basal 4 meters of the KP1 subunit of the KPF as it appears in the Beck Canyon region, Kingston Range, California. We describe and correlate sedimentary rocks at and immediately overlying the contact and analyze the sedimentary structures, textures and sequences. We have found only three sites in the northern …


Spatial Trends And Facies Distribution Of The High-Energy Alluvial Cutler Formation, Southeastern Utah, Isaac John Allred 2016 Brigham Young University

Spatial Trends And Facies Distribution Of The High-Energy Alluvial Cutler Formation, Southeastern Utah, Isaac John Allred

Theses and Dissertations

The Cutler Formation is composed of thick, arkosic, alluvial conglomerate, sandstone, and mudstone shed southwestward from the Uncompahgre Uplift into the Paradox Basin. More basin-ward the Cutler is recognized as a group consisting of differentiable formations. Discrete formations historically have not been distinguished near the uplift, but this study identified several separate successions in the Richardson Amphitheater. Research at the Richardson Amphitheater, ~12 km southwest of the uplift and ~30 km northeast of Moab, Utah, led to a systematic subdivision of the Permian Cutler Formation proximal to the uplift. Likely driven by channel cutting and migration across the alluvial fan, …


Geochemistry Of The Fluorine- And Beryllium-Rich Spor Mountain Rhyolite, Western Utah, Shane Robert Dailey 2016 Brigham Young University

Geochemistry Of The Fluorine- And Beryllium-Rich Spor Mountain Rhyolite, Western Utah, Shane Robert Dailey

Theses and Dissertations

The Miocene rhyolites of the Spor Mountain Formation hosts the world's largest beryllium deposit which produced 85% of the world's beryllium in 2010. The fresh lava is extremely enriched in Be (up to 75 ppm in matrix glass). We have examined the rhyolite to understand the Be enrichment. The Spor Mountain rhyolite contains ~40% quartz, ~40% sanidine, ~10% biotite, and ~10% plagioclase, along with accessory fluorite, columbite, euxenite, fergusonite, monazite, thorite, and zircon. Two types of rhyolite erupted within the Spor Mountain Formation, a less evolved magma (1150 ppm Rb, 42 ppm Be, 0.68 wt% F in matrix glass) and …


Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook 2016 Brigham Young University

Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook

Theses and Dissertations

The purpose of this study is to analyze the sedimentology and stratigraphy of the Middle Jurassic Preuss Sandstone and re-evaluate past sedimentological interpretations. The Preuss is located in northern Utah, western Wyoming and eastern Idaho and is stratigraphically equivalent to the Entrada Sandstone, which is Callovian in age (Dossett et al., 2014). This study is the first attempt at 1) a sequence stratigraphic framework, 2) a petroleum system analysis and 3) an extraterrestrial analog study for the Preuss. This study frames the Preuss within three broad facies groups: marine, coastal and terrestrial. The marine group includes the open marine and …


In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr 2016 U.S. Geological Survey Patuxent Wildlife Research Center

In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr

United States Geological Survey: Staff Publications

Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000-3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of …


Channel Flow Studies Using Driftwood Density Analysis In Elger Bay, Camano Island, Wa, Rebeca Becerra, Jasmine Bates, Clairissa De La Vergne 2016 CWU

Channel Flow Studies Using Driftwood Density Analysis In Elger Bay, Camano Island, Wa, Rebeca Becerra, Jasmine Bates, Clairissa De La Vergne

Symposium Of University Research and Creative Expression (SOURCE)

Previous studies on Elger Bay, Camano Island, WA hypothesized that the bay has been emptying of stored driftwood since the 1970's. To test this hypothesis, we conducted a research project using a combination of field data and historical imagery analysis with Google Earth and ArcGIS to mathematically compare the density of driftwood. Changes in driftwood area may indicate changes in sea level rise, bay subsidence, and/or anthropogenic activity. We found that the maximum driftwood extent was actually closer to the 1950's than the 1970's. In addition to overall extent we investigated the overall channel flow along Elger Bay by analyzing …


The Spatial Distribution And Origins Of Sandstone Monoliths In The Swauk Watershed, Kittitas County, Wa, Rebeca Becerra, Daniel O'Dell 2016 CWU

The Spatial Distribution And Origins Of Sandstone Monoliths In The Swauk Watershed, Kittitas County, Wa, Rebeca Becerra, Daniel O'Dell

Symposium Of University Research and Creative Expression (SOURCE)

Large groups of gigantic sandstone and conglomerate monoliths populate the Swauk Watershed of northern Kittitas County. These monoliths rest on side slopes in the watershed and distinctively project from their surroundings. The origins of these features are unknown. We studied these monoliths in the field by mapping their spatial distribution, describing their morphology and composition, and measuring their orientation and sizes in order to determine their origins. We used Google Earth and topographic maps to locate the monoliths and map their distribution. Interpretations were based from field work data and past research. Our field results show commonalities between the features …


Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres 2016 Stephen F Austin State University

Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres

Electronic Theses and Dissertations

Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that directly …


Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, Wesley L. Turner 2016 Stephen F Austin State University

Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, Wesley L. Turner

Electronic Theses and Dissertations

Transitional sediments on carbonate ramp slopes act as a link to relatively well-studied platform and basin depositional environments. In the southern Midland Basin, the key to understanding the relationship between these environments lies in the allochthonous gravity flow sediments found on the slope. Here, a succession of various gravity flow deposits is used to interpret how base level fluctuations affect the type of deposits found on the slope and their effect on the deep basinal environment. This study utilizes core samples from the Wolfcamp Formation adjacent to the Central Basin Platform in five wells in Northwest Crockett County, Texas. The …


An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner 2016 Stephen F Austin State University

An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner

Electronic Theses and Dissertations

The Owl Mountain Province is located within the Fort Hood Military Installation, an approximately 880 km2 installation established in the 1940s in Bell and Coryell counties, Texas, which has undergone extensive land use changes associated with military training, maintaining much of the vegetation in early succession. This study investigates thelithologic, stratigraphic, and structural controls on the hydrologic, hydrogeologic, and geomorphologic evolution of the Owl Mountain Province as expressed by mesic vegetation communities, including Pleistocene relicts Acer grandidentatum, within karst terrains. These systems exhibit complexly overprinted speleogenetic evolutions within a dynamic groundwater regime resulting from regional climate shifts throughout the …


High-Frequency Tectonic Sequences In The Campanian Castlegate Formation During A Transition From The Sevier To Laramide Orogeny, Utah, U.S.A., David B. Cross 2016 University of New Orleans

High-Frequency Tectonic Sequences In The Campanian Castlegate Formation During A Transition From The Sevier To Laramide Orogeny, Utah, U.S.A., David B. Cross

LSU New Orleans Theses and Dissertations

Though stratigraphic correlations are abundant in the Cordilleran basin-fill, they rarely include along-strike transects providing a spatio-temporal sense of deformation, sediment-supply and subsidence. A new, high-resolution, regional strike-correlation of the Castlegate Formation reveals progressive northward-growth of the San Rafael Swell during two embryonic episodes of Laramide-style deformation in central Utah. The intrabasinal deformation-events produced gentle lithospheric-folding punctuated by erosional-truncation of upwarped regions. The earliest episode occurred at 78 Ma in the southern San Rafael Swell likely causing soft-sediment deformation and stratal-tilting. Following this the alluvial-plain was leveled and rapid, extensive-progradation took place. A second episode, at 75 Ma, where deformation …


Applying Modern Interpretation Techniques To Old Hydrocarbon Fields To Find New Reserves: A Case Study In The Onshore Gulf Of Mexico, U.S.A., Josiah D. Hulsey 2016 LSU New Orleans

Applying Modern Interpretation Techniques To Old Hydrocarbon Fields To Find New Reserves: A Case Study In The Onshore Gulf Of Mexico, U.S.A., Josiah D. Hulsey

LSU New Orleans Theses and Dissertations

This study shows how the use of modern geological investigative techniques can reopen old, “drained” hydrocarbon fields. Specifically, it looks at the White Castle Field in South Louisiana. This field has pay sections ranging from late Oligocene to late Miocene. The late Oligocene package is underexplored and understudied and contains 3 primary reservoirs (Cib Haz (CH), MW, and MR). This study established the depositional history of these reservoirs. During most of the late Oligocene, the White Castle Salt Dome was located in a minibasin on the continental slope. The CH and MW deposited in this minibasin. The CH is an …


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