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Articles 331 - 360 of 408
Full-Text Articles in Geology
Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors
Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors
Geology Faculty Publications and Presentations
Mountain glaciers integrate climate processes to provide an unmatched signal of regional climate forcing. However, extracting the climate signal via intercomparison of regional glacier mass-balance records can be problematic when methods for extrapolating and calibrating direct glaciological measurements are mixed or inconsistent. To address this problem, we reanalyzed and compared long-term mass-balance records from the US Geological Survey Benchmark Glaciers. These five glaciers span maritime and continental climate regimes of the western United States and Alaska. Each glacier exhibits cumulative mass loss since the mid-20th century, with average rates ranging from −0.58 to −0.30 m w.e. a−1. We produced a …
Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data: Dataset, Ryan G. Smith, R. Knight
Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data: Dataset, Ryan G. Smith, R. Knight
Research Data
Supporting dataset for article published in Water Resources Research, Volume 55, Issue 4, pages 2801-2819
Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner
Honors Theses
Foreland basin sediment deposition in North-Central Pennsylvania during Late Devonian time records erosion of hinterland source terranes exhumed during regional plate convergence, including the collisional Acadian orogeny. The Catskill clastic wedge preserves a coarsening-upwards stratigraphic succession from marine to fluvial environments associated with sediment progradation and sea-level regression, yet depositional timescales and quantitative provenance data are largely unconstrained.
Detailed facies analysis of eight outcrops spanning >2 km of stratigraphy in Lycoming Co., Pennsylvania documents distinct upsection changes, interpreted to reflect changes in depositional environments consistent with previous sedimentology of the Catskill clastic wedge. Stratigraphy displays a transition from nearshore marine …
Identifying Key Factors Affecting Translational Landslides In Part Of The Yakima Fold And Thrust Belt, Washington State, Joseph Schilter
Identifying Key Factors Affecting Translational Landslides In Part Of The Yakima Fold And Thrust Belt, Washington State, Joseph Schilter
All Master's Theses
Washington has one of the fastest growth rates in the nation, and unfortunately also is among the most landslide-prone states. With increased population density and urban sprawl, the need for landslide hazard assessment grows. On the Columbia Plateau in central Washington, the smooth rigid, inclined surfaces of the Columbia River Basalts (CRBs) with loose sediment layers between them induces landslides of large blocks of bedrock. These hazards remain poorly understood, but their significance was heightened by the 2017 Rattlesnake Hills Landslide that currently threatens a community and an interstate highway south of Yakima, Washington. I propose that the strongest influences …
Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona
Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona
All Master's Theses
Records of past tsunamis help constrain the long-term characteristics of megathrust earthquakes and elucidate the role of sea-level in the preservation of tsunami deposits. Near Queule, south-central Chile (39.3˚S, 73.2˚W), three sand layers interpreted as tsunami deposits are interbedded with dark, organic-rich, silt deposits along a tidal channel landward of a sand spit capped by eolian sand dunes. The uppermost sand layer is attributed to the tsunami from the Mw 9.5 1960 earthquake. The sand layer is widespread, tabular, oxidized, thins landward, and generally occurs at a depth of <20 cm. The spatial distribution of the deposit corresponds closely with the extent of the 1960 tsunami sand on 1961 aerial photographs. We computed numerical simulations of the 1960 tsunami in Queule using the GeoClaw finite-slip hydrodynamic model based on three published earthquake sources. The simulations showed inundation up to 4km inland that overtopped the coastal dunes; agreeing with historical documentation and testimonies of 1960 tsunami survivors. Stratigraphically below the 1960 tsunami deposit are two tabular, landward-thinning sand layers with sharp lower contacts above silty organic-rich layers. Combined radiocarbon ages of seeds, charcoal and wood fragments found at the contacts with the underlying organic layers yielded ages of 5460-5320 and 5990-5910 cal. years BP. These sand layers have similar distribution patterns to the 1960 sand layer, but are finer grained, thinner and less oxidized. Below this sequence of interbedded tsunami sands and silty organic layers there is an abrupt contact underlain by a distinct sequence of four inorganic silt layers alternating with dark brown organic-rich silts, which are older than 6280-6110 cal. years BP. The deepest studied layer is a thick, fine, gray sand. We interpret the gray sand as a submarine environment during the mid-Holocene sea-level high stand, and the alternating inorganic and organic silts as tidal to shallow sub-tidal environments, possibly indicating co-seismic land-level changes. Gradual sea level fall after the deposition of the two paleotsunami sand deposits that changed the geomorphology of the coast and limited the accommodation space necessary to preserve additional overwash sediments could explain the 5000-year hiatus with no evidence of earthquakes or tsunamis. Further research will offer possible explanations for the exception of the 1960 tsunami in breaking this long-term pattern.
Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad
Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad
All Master's Theses
The causes and timing of cycles of aggradation and incision in the Hanson Creek drainage in central Washington provide insight into changes in channel morphology and paleoenvironment within the region over the last 8000 years. Stratigraphically and spatially coincident archaeological evidence reveals information related to human occupation during the latter half of the epoch. Using LiDAR imagery and field surveys, recent processes such as degree of modern channel incision, accumulation of valley floor sediment, channel morphology and gradient were evaluated. The spatial distribution of these channel characteristics was assessed in relation to proximal landforms such as colluvial deposits, basalt outcrops, …
Archaeological Investigation Using Geophysical Methods To Locate Historic Byram's Ford Road, Marshall Seth Foster
Archaeological Investigation Using Geophysical Methods To Locate Historic Byram's Ford Road, Marshall Seth Foster
Masters Theses
"Ground penetrating radar, a time domain electromagnetic metal detector and a frequency domain electromagnetic metal detector were used with the goal of locating a section of the Byram's Ford Road believed to be intersecting the historic Big Blue Battlefield in the Westport area of Kansas City, Missouri.
Ground penetrating data were acquired at three sites, Site A, Site B, and Site C. The time domain EM metal detector was used to acquire data at Site A, where subsequent ground truthing was conducted using the frequency domain EM metal detector and an excavation tool. Significant anomalies were visible on both the …
Exploration For Alteration Halos Around The Ag-W Deposits In Southeastern Missouri, Usa, Daniel Joseph Warbritton
Exploration For Alteration Halos Around The Ag-W Deposits In Southeastern Missouri, Usa, Daniel Joseph Warbritton
Masters Theses
"The St. Francois Mountains in SE Missouri are an extensive terrane of granitic ring complexes and associated rhyolites. They were an important source of Ag, W, and Sn and mined intermittently from the 1800s until the 1950s. The Ag-W ores occur in the Silvermine Granite and rhyolite roof rocks. The deposits are classified as a xenothermal ore system with mineralization occurring in quartz veins and surrounding greisen (up to 2.5 m). Exploration for hydrothermal ore deposits often focuses on the identification of alteration halos in the surrounding host rocks. In the vast majority of xenothermal ore deposits, such as in …
Keweenaw Fault Geometry And Slip Kinematics - Bête Grise Bay, Keweenaw Peninsula, Michigan, Colin Tyrrell
Keweenaw Fault Geometry And Slip Kinematics - Bête Grise Bay, Keweenaw Peninsula, Michigan, Colin Tyrrell
Dissertations, Master's Theses and Master's Reports
The Keweenaw Fault (KF) has been interpreted as a rift-bounding normal fault along the southern margin of the Midcontinent Rift System; later inverted into a reverse fault by a tectonic compression event. The fault trends NNE to NE for most of its trace but curves clockwise to ESE along the Bête Grise Bay area in Michigan’s Keweenaw Peninsula. U.S. Geological Survey maps depict the KF along Bête Grise Bay as a continuous thrust that follows a sinuous contact between Portage Lake Volcanics (PLV) and Jacobsville Sandstone (JS). New fieldwork reveals a left-stepping en echelon system of ESE-trending faults connected by …
X-Ray Fluorescence Analysis Of Tuscaloosa Marine Shale Cuttings From Horizontally Drilled Wells, Xiaotian Wang
X-Ray Fluorescence Analysis Of Tuscaloosa Marine Shale Cuttings From Horizontally Drilled Wells, Xiaotian Wang
Electronic Theses and Dissertations
The Upper Cretaceous Tuscaloosa Marine Shale (TMS) is a gray to black fissile marine shale deposited at depth of between 10,000 and 20,000 ft near the ancient Gulf of Mexico. The TMS has been gradually developed as a hydrocarbon reservoir in the past several decades. But there are rare researches evaluating geochemical properties based on chemostratigraphy of the TMS. The objective of this research is to spatially evaluate geophysical properties and chemostratigraphy of the TMS, to characterize elemental changes along well paths and to evaluate the effect of basic sample clean on XRF results. The data available for this study …
Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez
Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez
Open Access Theses & Dissertations
For many years the use of thermal barrier coatings (TBC) in gas turbine engines has allowed a significant increase in engine operating temperatures which are above the Ni-based super alloys' melting point. The base material for TBCs is the state of the art 7 wt % yttria stabilized zirconia (YSZ) which provides the thermal protection. Current industry demands for increased engine efficiency has pushed TBCs to the limits where significant technological constrains have been identified. One of the main ones represents the high temperature corrosion of the TBC material due to the ingestion of silicate based airborne particles commonly referred …
The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur
The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur
Electronic Theses and Dissertations
The Medicine Hat Block (MHB) is one of the core cratonic elements that amalgamated in the Paleoproterozoic to form Laurentia. However the role of the MHB in the formation of Laurentia is poorly constrained due to virtually all of the MHB being concealed by Proterozoic and younger supracrustal sequences limiting availability of data. The primary sources of samples from the MHB are 1) xenoliths of variable metamorphic grade including gneisses amphibolites and meta-plutonic rocks collected from Eocene volcanic rock; and 2) similar lithologies recovered from boreholes that penetrate to the MHB basement. Previous work on samples from the MHB yielded …
Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey
Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey
Master's Theses or Doctor of Nursing Practice
Field reconnaissance examining the Permian Blaine Formation and the karst features within those rocks were conducted on two ranches in Barber County, Kansas. Karst features are developed dominantly in gypsum and include caves, sinkholes, losing streams, springs, and other surficial karst features. The Blaine Formation is known as a significant karst unit and major aquifer system in Oklahoma; however, little work has been conducted in Kansas. This study identifies the processes that lead to karst development in the Blaine Formation in Kansas and represents the first stage of a karst study to develop predictive karst models. This survey of caves …
Scanning Electron Microscope Study Of Microstructure And Regeneration Of Upper Pennsylvanian Cladid Crinoid Spines, Hannah Smith, James Thomka
Scanning Electron Microscope Study Of Microstructure And Regeneration Of Upper Pennsylvanian Cladid Crinoid Spines, Hannah Smith, James Thomka
Williams Honors College, Honors Research Projects
The crinoid skeleton is characterized by a complicated, highly porous microstructure known as stereom. Details of stereomic microstructural patterns are directly related to the distribution and composition of connective tissues, which are rarely preserved in fossils. However, certain portions of the crinoid skeleton have never been studied with respect to stereomic microstructure. In particular, spines are common features on the crowns of many Paleozoic crinoids but had not previously been studied in detail with respect to stereomic microstructure. This study focused on pirasocrinid cladid crinoids, a common group with numerous identifiable crown spines, including spines on the arms and anal …
Mineral Exploration Investigation In The Northern Sierra Madre Occidental, Mexico, Labdan Nijr Alqahtani
Mineral Exploration Investigation In The Northern Sierra Madre Occidental, Mexico, Labdan Nijr Alqahtani
Open Access Theses & Dissertations
The Sierra Madre region is rich in mineralized deposits, but it is hard to access because of the rugged terrain. Remote sensing and GIS can help in mineral exploration and regional structural analysis. The purpose of this project is to study linear, curvilinear, arcuate, and circular features in the Sierra Madre Occidental of Mexico in order to improve exploration possibility. It is of great interest to know the relationship between lineament intersections, caldera features because of the location of potential mineral occurrences. In this study, 4,445 lineaments were mapped manually using directional filters applied to satellite images. A total of …
Stratigraphic Response Of The Differential Rise Of The Gypsum Valley Salt Wall, Jurassic Entrada Formation, Paradox Basin, Colorado, Rafael Andres Delfin
Stratigraphic Response Of The Differential Rise Of The Gypsum Valley Salt Wall, Jurassic Entrada Formation, Paradox Basin, Colorado, Rafael Andres Delfin
Open Access Theses & Dissertations
The effect of halokinetic processes on fluvial and marine depositional environments adjacent to salt diapirs have been well established through extensive research, however eolian systems in similar geologic settings have not been documented. This has left a void in our understanding of eolian depositional environments adjacent to salt diapirs. This study is aimed at providing new knowledge and a solid foundation on eolian systems and diapiric processes. Despite our limited understanding of theses interactions, there has been a recent interest in deep water prospectively in the Gulf of Mexico. Successful tests of the Norphlet Formation prove that eolian sandstones deposited …
Sequence Stratigraphy, Diagenesis, And Depositional Facies Of An Exposed Megaflap: Pennsylvanian Hermosa Group, Gypsum Valley Salt Wall, Paradox Basin, Colorado, Kyle Thomas Deatrick
Sequence Stratigraphy, Diagenesis, And Depositional Facies Of An Exposed Megaflap: Pennsylvanian Hermosa Group, Gypsum Valley Salt Wall, Paradox Basin, Colorado, Kyle Thomas Deatrick
Open Access Theses & Dissertations
Outcrop exposures mostly of the Pennsylvanian Honaker Trail Formation provide a 2 km strike-oriented view of a megaflap on the southwestern flank of the Gypsum Valley salt wall, Paradox Basin, Colorado that serves as an outcrop analog for megaflaps recently drilled unexpectedly in the Gulf of Mexico and other salt basins worldwide. The near vertical (80-90°) stratal panel comprises a 60 m thick succession of non-evaporite facies of the Pennsylvanian upper Paradox Formation, overlain by a 117 m section of cyclic shallow marine carbonates and siliciclastics of the Honaker Trail Formation. Near vertical upper Paradox and Honaker Trail strata are …
Geophysical Studies Of The Three Sisters Andesite, West El Paso, Texas, Alexander D'Marco Garcia
Geophysical Studies Of The Three Sisters Andesite, West El Paso, Texas, Alexander D'Marco Garcia
Open Access Theses & Dissertations
The Three Sisters andesite intrusion is part of series of three small igneous bodies that crop out in western El Paso to the north of the more extensive intrusions found on the University of Texas at El Paso campus and at Mount Cristo Rey. These Oligocene age intrusions are believed to form part of a deeper, more extensive igneous body that may lie beneath much of western El Paso and the southern Mesilla Valley. I used several geophysical techniques to determine the size and shape of the Three Sisters intrusion to better understand its connection to other andesite outcrops and …
Structural And Sedimentological Analysis Of The Bear Canyon Conglomerate, Southeastern California: Implications For The Timing And Style Of Miocene Deformation Within The Eastern California Shear Zone, Garrett Goff
Open Access Theses & Dissertations
The region between Indian Pass and Picacho State Recreation Area (PSRA) in southeastern California records complex deformation related to the transition from a Paleogene convergent margin to a Neogene transform setting, although the timing and nature of youngest deformation in this region remains incompletely known. A 1.7 km-thick section of Miocene Bear Canyon conglomerate (BCC) was studied to constrain this young period of deformation. These rocks lie unconformably upon 23 Ma volcanic and epiclastic rocks and a Mesozoic metamorphic basement terrane. Near PSRA the BCC contains locally derived clasts and can be further subdivided into three unconformity-bounded sequences, referred to …
Origin And Characterization Of Intrasalt Non-Halite Lithologies Of The Neoproterozoic Patawarta Diapir, Central Flinders Ranges, South Australia, Rachelle A. Kernen
Origin And Characterization Of Intrasalt Non-Halite Lithologies Of The Neoproterozoic Patawarta Diapir, Central Flinders Ranges, South Australia, Rachelle A. Kernen
Open Access Theses & Dissertations
Non-halite lithologies in salt diapirs are variously referred to as clasts, chips, rafts, stringers, sutures, and encased minibasins in the literature. Due to the complexities of gathering and processing seismic reflection data within salt bodies, nonhalite intrasalt lithologies, collectively referred to as inclusions here, are often first identified while drilling wells. These wells may penetrate unexpected lithologies of unknown fluid pressure, which can result in economic failure and pose serious drilling hazards and a threat to human life. Therefore, it is imperative to identify and determine the nature of inclusions prior to drilling, and ideally during the well planning process …
Petrophysical, Geostatistical And Geo-Spatial Analysis Of Round Top Mountain Rhyolite (Hudspeth County, West Texas, Usa), Lorraine Marie Negron
Petrophysical, Geostatistical And Geo-Spatial Analysis Of Round Top Mountain Rhyolite (Hudspeth County, West Texas, Usa), Lorraine Marie Negron
Open Access Theses & Dissertations
This project consists of three separate projects that all investigate Round Top Mountain, a rhyolite laccolith located in Sierra Blanca, west Texas in Hudspeth County (U.S.A). The three projects will explore and analyze the petrophysical, geostatistical and geo-spatial aspects of this unique deposit.
Project 1:
This petrophysical study examines the porosity and micro-permeability of the Round Top rhyolite at a scale, roughly 5 to 10 mm or pebble sized, similar to anticipated heap leach crush sizes. Large voids and fluid paths, such as faults and joints in the massive rock (meter to km scale, boulder to outcrop size), are not …
Fault Kinematics Of The Southern Rio Grande Rift: Exploring The Possibility Of Fault Reactivation, Georgina Rodriguez Gonzalez
Fault Kinematics Of The Southern Rio Grande Rift: Exploring The Possibility Of Fault Reactivation, Georgina Rodriguez Gonzalez
Open Access Theses & Dissertations
The region in and around the southern Rio Grande rift has experienced a long and complex tectonic history since the Precambrian era. In addition to recording extension directions due to the opening of the Rio Grande rift, faults can also possibly record contractional deformation related to the Laramide orogeny, extension along the boundary of the Mesozoic Chihuahua Trough, and possibly strike - slip movement since the Precambrian related to the Texas Lineament. The northern and central segments of the Rio Grande rift preserve mostly N - S-trending faults, whereas the southern segment preserves NW - SE-trending faults. The main hypoThesis …
Precipitation And Transformation Of Iron-Sulfide Nanoparticles In Low-Temperature Aqueous Environment: Effects Of Reactant Iron And Sulfide Sources, Ezequiel A. Moreno Flores
Precipitation And Transformation Of Iron-Sulfide Nanoparticles In Low-Temperature Aqueous Environment: Effects Of Reactant Iron And Sulfide Sources, Ezequiel A. Moreno Flores
Open Access Theses & Dissertations
Iron sulfide nanoparticles assume an important role within a wide range of geological settings as indicators of redox environmental conditions and elemental cycling mechanisms. Initial precipitates of iron sulfide are exclusively nanoscale sized in low temperature aqueous conditions and have been reported to go through diverse morphological and phase transformations, possibly leading to the ultimate deposits of pyrite in geologic records of various times. A systematic understanding of how the early-stage nanoparticles of iron sulfide may develop into more crystalline iron sulfide forms is still lacking however. The major goal for this study was to illuminate the effects of the …
Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz
Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz
Open Access Theses & Dissertations
Technological advances in combination with the onslaught of data availability allow for large seismic data streams to automatically and systematically be recorded, processed, and stored. Here, we develop an automated approach to identify small, local earthquakes within these large continuous seismic data records. Our aim is to automate the process of detecting small seismic events triggered by a distant large earthquake, recorded at a single station. Specifically, we apply time-domain short-term average (STA) to long-term average (LTA) ratio algorithms to three-component data to create a catalog of detections. We remove some of the false detections by requiring the detection be …
Decision Making Under Uncertainty With Applications To Geosciences And Finance, Laxman Bokati
Decision Making Under Uncertainty With Applications To Geosciences And Finance, Laxman Bokati
Open Access Theses & Dissertations
In many practical situations, we need to make a decision. In engineering, we need to decide on the best design of a system, and, for existing systems â?? on the best control strategy. In financial applications, we need to decide what is the best way to invest money. In geosciences, we need to decide whether we should explore a possible mineral deposit â?? or whether we should perform more experiments and measurements (and what exactly). In some cases, we can compute the exact consequences of each decision - e.g., if we are controlling a satellite. However, in many other cases, …
Interactions Of Bacterial Communities With Hydrous Sulfate Minerals In Water-Restricted Gypsic Environments: A Case Study Based In The White Sands National Monument, Brandon Nicholas Lajoie
Interactions Of Bacterial Communities With Hydrous Sulfate Minerals In Water-Restricted Gypsic Environments: A Case Study Based In The White Sands National Monument, Brandon Nicholas Lajoie
Open Access Theses & Dissertations
Microbial communities have been commonly found to survive and thrive in arid to hyper-arid gypsic environments that are considered hostile to most other forms of life. The mechanisms through which microbes have conquered these harsh environments remain poorly understood. Here I hypothesize that the microbial communities in water-restricted gypsic settings could benefit in terms of energy and water sources via their interactions with the abundant hydrous sulfate minerals [i.e., gypsum (CaSO4·2H2O)] that build up these niches. Gypsum is of high bio-relevance because its sulfate component may be used as electron acceptor by sulfate-reducing bacteria and the crystallization water may be …
Zircon (U-Th)/He Thermochronologic Investigation Of The Long-Term Thermal History Of Proterozoic Rocks In West Texas And Southern New Mexico, Nathan Zachary Reade
Zircon (U-Th)/He Thermochronologic Investigation Of The Long-Term Thermal History Of Proterozoic Rocks In West Texas And Southern New Mexico, Nathan Zachary Reade
Open Access Theses & Dissertations
The tectonic history of west Texas and southern New Mexico is well documented, however existing geologic data only provide limited snapshots of the regions prolonged and complex tectonic evolution. Zircon (U-Th)/He (ZHe) thermochronology is used to examine the long-term thermal history of Proterozoic rocks exposed in the southern Rio Grande rift. ZHe data were collected from the Carrizo Mountains (10 dates), Cookes Range (16 dates), and Franklin Mountains (30 dates) in order to constrain the long-term (>1 Ga) thermal history of rocks in this region and relate this history to known tectonic or climatic events. Individual ZHe dates range …
Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia
Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia
Open Access Theses & Dissertations
This study provides new insights into the geometry and timing of ductile, syn-metamorphic structures in the central Panamint Mountains of eastern California. The study focused on Surprise Canyon, where exposures of Meso- to Neoproterozoic miogeocline rocks, reworked crystalline basement, and syn-metamorphic granitoids record fabric overprints indicative of at least two distinct dynamo-thermal metamorphic events. Prograde metamorphism at greenschist and amphibolite metamorphic facies conditions occurred during Early Jurassic plutonism based on deformation of a dioritic pluton with a U-Pb date reported here of 175.6 ± 3.2 Ma. Mid Jurassic deformation (D1) generated the main continuous cleavage in the rocks (S1) as …
Glacial Deposits, Vol. 44, 2019, Department Of Geography, Geology, And The Environment
Glacial Deposits, Vol. 44, 2019, Department Of Geography, Geology, And The Environment
Glacial Deposits
Newsletter of the Department of Geography, Geology, and the Environment
Structural Controls And Depositional Environments Of The Glen Rose Subgroup In Pelahatchie Field In Rankin County, Mississippi, Chesney Petkovsek
Structural Controls And Depositional Environments Of The Glen Rose Subgroup In Pelahatchie Field In Rankin County, Mississippi, Chesney Petkovsek
Electronic Theses and Dissertations
Following Lion Oil’s drilling of the Sowell #1, Lower Cretaceous step-out drilling in Pelahatchie Field has led to the establishment of Mooringsport, Paluxy, Rodessa, Sligo, and Hosston oil and gas condensate production along the flanks and crest of a salt feature within Rankin County, Mississippi. Exploration of salt features has been intermittent throughout Mississippi, but has shifted from targeting pay zones along the crests of domal and piercement salt features in the 1940s, to targeting reserves along the flanks of these features in the 1970s. The dominant structural feature in Pelahatchie Field is an elongate north-south-trending salt ridge. Results of …