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Kinematic And Vorticity Analysis Of The Slide Lake And Homestake Shear Zones, Central Colorado, Carsen T. Adams 2022 University of Tennessee, Knoxville

Kinematic And Vorticity Analysis Of The Slide Lake And Homestake Shear Zones, Central Colorado, Carsen T. Adams

Masters Theses

Kinematic and quantitative vorticity analysis of the Homestake shear zone (HSZ) and the Slide Lake shear zone (SLSZ) in central Colorado provide further insight into crustal processes that controlled deformation within the Colorado Mineral Belt (CMB) shear zone system throughout the Proterozoic. Evaluating vorticity, that is, the relative contributions of pure to simple shear in sheared rocks, is crucial to understanding lithospheric tectonic evolution and allows for kinematic modeling of shear zone development at a variety of scales. Moreover, novel vorticity analyses involve determining the orientation of the vorticity vector and vorticity normal surface which can give insight into shear ...


Response Of Surface And Atmospheric Parameters Associated With The Iran M 7.3 Earthquake, Feng Jing, Ramesh P. Singh 2022 China Earthquake Administration

Response Of Surface And Atmospheric Parameters Associated With The Iran M 7.3 Earthquake, Feng Jing, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Multiparameter observed from satellite, including microwave brightness temperature, skin temperature, air temperature, and carbon monoxide, have been analyzed to identify the anomalous signals associated with the M 7.3 Iran earthquake of November 12, 2017. Besides removing the multiyear variability of parameters as background, the effect of surface and atmosphere of a dust storm event in Middle East region during October 29–November 1 is considered to distinguish the possible anomalies associated with the earthquake. The characteristic behaviors of surface and atmospheric parameters clearly show the signals associated with the M 7.3 earthquake and the dust storm event. The ...


Deformation Conditions Of Quartz-Rich Mylonites Of The Grenville Front Tectonic Zone And Application To The Crustal Strength, Xueke Chang 2022 The University of Western Ontario

Deformation Conditions Of Quartz-Rich Mylonites Of The Grenville Front Tectonic Zone And Application To The Crustal Strength, Xueke Chang

Electronic Thesis and Dissertation Repository

This thesis analyzes a suite of mylonites from the Grenville Front shear zone exposed southeast of Sudbury, Ontario. Lattice preferred orientations, titanium-in-quartz thermometer, and dynamically recrystallized grain size piezometer measurements were applied to obtain the deformation mechanisms, deformation temperatures (T), and differential stresses (σ), respectively. Results show that these mylonites were formed in the shear zone during the terminal stage of the Grenville Orogeny. The dominant deformation mechanism is by regime 2 dislocation creep. The deformation temperature is between 425-567 °C, and the differential stress is between 56-133 MPa. These results are discussed in the context of wet quartzite flow ...


Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black 2022 The University of Southern Mississippi

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the ...


Bathymetry Based Modeling Of Subaxial Magma Flows Under The Mid-Atlantic Ridge, 0 To 30° N, Adam R. Tjoelker, Neil Van Kanegan, Simon Detmer, C. Renee Sparks 2022 Calvin University

Bathymetry Based Modeling Of Subaxial Magma Flows Under The Mid-Atlantic Ridge, 0 To 30° N, Adam R. Tjoelker, Neil Van Kanegan, Simon Detmer, C. Renee Sparks

The Compass: Earth Science Journal of Sigma Gamma Epsilon

Fracture patterns of the Mid-Atlantic Ridge (MAR) provide evidence of tectonic forces related to divergence and magma upwelling at the ridge axis. In this study, we focus on the MAR from 0 to 30° N, where the N-S ridge exhibits slow spreading rates (2-4 cm/yr) and pronounced axial topography. Ridge segments and transform faults identified in bathymetry data were analyzed for strike orientation and axial depth profiles. Azimuths of transform faults and ridge segments exhibit increasing clockwise rotation with latitude, and all have left lateral displacement. Bathymetric sampling along ridge segments occurred at 9 km intervals with 20 km ...


Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld 2022 Union College - Schenectady, NY

Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld

Honors Theses

We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth and find that surface temperature has the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram ...


Pronounced Changes In Thermal Signals Associated With The Madoi (China) M 7.3 Earthquake From Passive Microwave And Infrared Satellite Data, Feng Jing, Lu Zhang, Ramesh P. Singh 2022 China Earthquake Administration

Pronounced Changes In Thermal Signals Associated With The Madoi (China) M 7.3 Earthquake From Passive Microwave And Infrared Satellite Data, Feng Jing, Lu Zhang, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Thermal variations in surface and atmosphere observed from multiple satellites prior to strong earthquakes have been widely reported ever since seismic thermal anomalies were discovered three decades ago. These thermal changes are related to stress accumulation caused by the tectonic activities in the final stage of earthquake preparation. In the present paper, we focused on the thermal changes associated with the 2021 Madoi M 7.3 earthquake in China and analyzed the temporal and spatial evolution of the Index of Microwave Radiation Anomaly (IMRA) and the Index of Longwave Radiation Anomaly (ILRA) based on 8-year microwave brightness temperature (MWBT) and ...


Processing Seismic, Gravity And Magnetic Data Over Diebold Knoll On Juan De Fuca Plate, Md Ariful Islam, Irina Filina 2022 University of Nebraska-Lincoln

Processing Seismic, Gravity And Magnetic Data Over Diebold Knoll On Juan De Fuca Plate, Md Ariful Islam, Irina Filina

UNL Student Research Days Posters, Graduate

The Juan de Fuca plate is subducting beneath the North American plate along the Cascadia Subduction Zone. The CSZ is associated with multiple earthquakes, although compared to other subduction zones, it is less active. Many studies suggest that subduction will cause major mega thrust earthquake in near future, while others oppose this view. This project is focused on the Diebold Knoll on the JdF plate Various geophysical methods will be integrated to determine its origin and tectonic history.


Regional Correlation And Depositional History Using Well Log And Core Data Of The Geneseo-Burket From The Poseidon 8m Well, Westmoreland County Pa, Usa, Spencer Leonard Williams Jr. 2022 West Virginia University

Regional Correlation And Depositional History Using Well Log And Core Data Of The Geneseo-Burket From The Poseidon 8m Well, Westmoreland County Pa, Usa, Spencer Leonard Williams Jr.

Graduate Theses, Dissertations, and Problem Reports

Abstract

Regional Correlation and Depositional History using Well Log and Core Data of the Geneseo-Burket from the Poseidon 8M Well, Westmoreland County PA, USA



Spencer Williams

Natural gas producers have invested billions of dollars in Pennsylvania and West Virginia to establish significant gas production from the Devonian Marcellus Shale and the deeper Ordovician Utica-Point Pleasant interval. In addition, commercial gas production has been reported from several other Devonian shale units in the Appalachian region, including the Rhinestreet, Levanna, and Geneseo-Burket. The Marcellus Shale is the largest natural gas play in the United States. The Marcellus is located directly under the ...


Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger 2022 University of Kentucky

Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger

Theses and Dissertations--Earth and Environmental Sciences

Although deformation related to salt tectonics is generally considered to be an ancillary field of structural geology, owing to its relatively limited occurrence in the geologic record, the preponderance of salt-involved systems in multiple hydrocarbon-rich basins around the world (e.g., Gulf of Mexico, Atlantic passive margins, Iran, etc.) creates a necessity for understanding salt-related deformation. Traditionally, salt was considered to be relatively weak and thus was mostly unable to drive deformation of adjacent wall rocks and cover sequences. However, a number of recent numerical modeling studies have shown that mobilized and pressurized salt may have the ability to actively ...


Influence Of Bedrock Erodibility On Orogen Evolution In Collisional Systems And Implications For Geodynamic Models, Stephanie Ann Sparks 2022 University of Kentucky

Influence Of Bedrock Erodibility On Orogen Evolution In Collisional Systems And Implications For Geodynamic Models, Stephanie Ann Sparks

Theses and Dissertations--Earth and Environmental Sciences

Theoretical and numerical geodynamic models of continental collisional systems often involve, either explicitly or implicitly, a necessary yet complicated dependence between tectonics and erosion; however, the exact nature of these relationships remains elusive and controversial. In such models for the Himalayan-Tibetan (H-T) collisional orogen, surface processes are theorized or in some cases required to play an essential role in modulating critical processes active in the evolution of that system. To investigate, at least to first order. these interactions between climate and tectonics, we generate a simplified landscape evolution model of an actively uplifting orogenic wedge acted upon by surface processes ...


Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer 2022 University of Kentucky

Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer

Theses and Dissertations--Earth and Environmental Sciences

This dissertation is composed of three distinct manuscripts which collectively investigate processes that contribute to the late evolution of collisional mountain systems —specifically, the ancient Appalachian-Caledonian system. In the first paper, 40Ar/39Ar thermochronological data are used to constrain the timing of exhumation of the Scandian orogenic wedge of northern Scotland. Muscovite and amphibole samples yield dates of ca. 420-411 Ma, consistent with cooling after peak orogenesis. During this cooling phase, dates from both systems in individual thrust sheets show an increase in cooling rate in the later stage of exhumation; in the orogenic core, the cooling rate ...


Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom 2022 West Virginia University

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching ...


Geology Of The Porter Gap 7.5–Minute Quadrangle, Alabama, And Stretched Pebble Analysis Within The Western Blue Ridge Of The Southern Appalachians, Tessa Mills 2022 Missouri State University

Geology Of The Porter Gap 7.5–Minute Quadrangle, Alabama, And Stretched Pebble Analysis Within The Western Blue Ridge Of The Southern Appalachians, Tessa Mills

MSU Graduate Theses

The Porter Gap 7.5–minute quadrangle in eastern Alabama contains portions of the undifferentiated sedimentary Knox Group of the Valley and Ridge province, the metamorphic Talladega Group of the western Blue Ridge, and the metamorphic Ashland Supergroup of the eastern Blue Ridge. Three major faults separate the rock units, including the Talladega-Cartersville fault, the Hillabee thrust fault, and the Hollins Line fault. Deformation and metamorphism of rocks within the Talladega Group occurred during the middle to late Mississippian (~334–320 Ma) recorded by stretched pebbles within the Cheaha Quartzite member of the Lay Dam Formation. Stretched pebbles within the ...


Viscous Anisotropy Of Wet Olivine Aggregates, Megan Ryan 2022 The University of Akron

Viscous Anisotropy Of Wet Olivine Aggregates, Megan Ryan

Williams Honors College, Honors Research Projects

I will deform natural olivine aggregates (Anita Bay dunite) cores in various orientations relative to a natural mineral alignment in the rock under both dry and wet conditions. Different orientations in regards to this mineral alignment will produce deformation on different slip systems. Stress measurements will be taken during the deformation of the samples in order to characterize any changes in viscous anisotropy observed due to the changes in slip system. Anita Bay dunite is a proxy for the main mineral found in the mantle wedge of subduction zones. Therefore, understanding the transformation of viscosity and slip systems in this ...


Geology Of The Jacksonville 7.5 Minute Quadrangle And U–Pb And (U–Th)/He Reveal Sediment Routing And Uplift In The Southern Appalachian Valley And Ridge Province, Derek L. Spurgeon 2022 Missouri State University

Geology Of The Jacksonville 7.5 Minute Quadrangle And U–Pb And (U–Th)/He Reveal Sediment Routing And Uplift In The Southern Appalachian Valley And Ridge Province, Derek L. Spurgeon

MSU Graduate Theses

The southern Appalachian Mountains have experienced multiple deformation events having undergone two full Wilson cycles. The foreland Valley and Ridge province is composed of sedimentary Paleozoic rock that range in age from earliest Cambrian to Middle Pennsylvanian. This sedimentary basin was intensely folded and faulted during the collision of Gondwana during the Middle to Late Carboniferous Period. From previous geologic structural mapping that has taken place, some large-scale structures in the Valley and Ridge Province seem to be out of sequence. To better understand the relationships in these structures, geologic mapping in high detail at the 1:24,000 scale ...


U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin 2022 Missouri State University

U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin

MSU Graduate Theses

The Salmon River suture zone in west-central Idaho, USA records the tectonic processes where island arcs, similar to modern-day Japan, were accreted to the North American continent in the Jurassic and Cretaceous periods (160-90 million years ago). This suture zone contains metamorphic rocks that were buried deep within the crust at depths of 20 kilometers or more and have subsequently been brought to the surface. The exhuming processes responsible for the metamorphic rocks in the Salmon River suture zone remains unclear. Two competing hypotheses have been proposed to explain the transport of the rocks from the Salmon River suture zone ...


Dynamic Relationship Study Between The Observed Seismicity And Spatiotemporal Pattern Of Lineament Changes In Palghar, North Maharashtra (India), Biswajit Nath, Ramesh P. Singh, Vineet K. Gahalaut, Ajay P. Singh 2021 University of Chittagongc

Dynamic Relationship Study Between The Observed Seismicity And Spatiotemporal Pattern Of Lineament Changes In Palghar, North Maharashtra (India), Biswajit Nath, Ramesh P. Singh, Vineet K. Gahalaut, Ajay P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Palghar region (north Maharashtra, India), located in the northwestern part of the stable continental region of India, experienced a low magnitude earthquake swarm, which was initiated in September 2018 and is continuing to date (as of October 2021). From December 2018 to December 2020, ~5000 earthquakes with magnitudes from M1.2 to M3.8 occurred in a small region of 20 × 10 km2. These earthquakes were probably triggered by fluid migration during seasonal rainfall. In this study, we have used multi-temporal Landsat satellite data of the year 2000, 2015, 2018, 2019, and 2020, extracted lineaments, and studied the ...


Spatial Variations Of Stochastic Noise Properties In Gps Time Series, Xiaoxing He, Michael Simon Bos, Jean-Philippe Montillet, Rui Fernandes, Timothy I. Melbourne, Weiping Jiang, Wudong Li 2021 Jiangxi University of Science and Technology

Spatial Variations Of Stochastic Noise Properties In Gps Time Series, Xiaoxing He, Michael Simon Bos, Jean-Philippe Montillet, Rui Fernandes, Timothy I. Melbourne, Weiping Jiang, Wudong Li

Geological Sciences Faculty Scholarship

The noise in position time series of 568 GPS (Global Position System) stations across North America with an observation span of ten years has been investigated using solutions from two processing centers, namely, the Pacific Northwest Geodetic Array (PANGA) and New Mexico Tech (NMT). It is well known that in the frequency domain, the noise exhibits a power-law behavior with a spectral index of around −1. By fitting various noise models to the observations and selecting the most likely one, we demonstrate that the spectral index in some regions flattens to zero at long periods while in other regions it ...


Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom 2021 Dartmouth College

Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom

Other Staff Materials

Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other ...


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