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Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …

Geology Study – Drilling Down At Red Trail Energy, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about a 2019–2020 geophysical survey near Richardton, North Dakota. The survey investigated the area’s feasibility as a CO₂ storage site, as part of the Red Trail Energy carbon capture and storage (CCS) research effort. Summarizes survey process and results. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

A Study Of Structures In The Magnetic Basement In The Reelfoot Rift And Surrounding Region, Christopher Marlow

Electronic Theses and Dissertations Archive

We apply multiple filters to aeromagnetic intensity data to visualize the magnetic signature of eastern Reelfoot rift margin basement rocks. We interpret the eastern Reelfoot rift margin to be segmented into nine intersecting faults. We calculate the moment magnitude potential of each fault based on the estimated fault length. The minimum moment magnitude potential is 6.0, and the maximum is 7.0.The Crittenden County fault zone is a potentially active fault zone located within 25 km of Memphis, Tennessee, and poses a significant seismic hazard to the region. To improve our understanding of the structure of both fault systems in this …

Bedrock Topography Mapping Of The East Leroy And Climax 7.5’ Quadrangles, Mi Using Hvsr And Other Geophysical Methods, Tyler A. Norris

Masters Theses

Geophysical methods were used to estimate bedrock depths below sedimentary cover and infer previously unknown features in two adjacent topographic quadrangles (Climax & East Leroy) in Michigan, USA. The study area contains mostly Mississippian Shale bedrock overlain by Wisconsin-aged glacial drift deposited during multiple glacial advances and retreats of the Saginaw Lobe (Laurentide Ice Sheet). These glacial events created complex landform assemblages that have only recently been mapped in detail near-surface, but are still poorly understood in the subsurface. Buried bedrock valleys typically contain coarse glacial sediment and thus are valuable aquifers, but these can be difficult to locate due …

Detection Of Bedrock Fractures And Joints Beneath Cover: Geophysical Approaches To An Engineering Geology Problem, Muthanna Yousif Yaqoob Aldiney

Dissertations

This research used geophysical methods to detect the presence of sub-vertical failure planes, their direction(s), and their frequency in bedrock beneath soil or glacial drift overburden. Azimuthal measurements using the seismic, electrical resistivity (ER), and electromagnetic conductivity were made to evaluate which techniques might provide the best indication of the bedrock joints, faults, or shear zones. Measurements were made at multiple sites near each of three locations: Jackson, Alpena, and Grand Ledge, Michigan. The first two are former limestone quarries and the third is underlain by sandstone. Seismic measurements began with one or two linear refraction spreads, used to establish …

Geophysical Characterization Of A Rare Earth Element Enriched Carbonatite Terrane At Mountain Pass, California Eastern Mojave Desert, Kevin Denton

Master's Theses

Mountain Pass, California, located in the eastern Mojave Desert, hosts one of the world's richest rare earth element (REE) deposits. The REE-rich rocks occur in a 2.5 km- wide, north-northwest trending zone of Mesoproterozoic (1.4–1.42 Ga) stocks and dikes, which intrude a larger Paleoproterozoic (1.7 Ga) schist-gneiss terrane that extends ~10 km southward from Clark Mountain to the Mescal Range. Several REE-enriched bodies make up the Mountain Pass intrusive suite including shonkinite, syenite, and granite comprising an ultrapotassic intrusive suite and the Sulphide Queen carbonatite body.

Two-dimensional modeling of gravity, magnetic, and electrical resistivity data reveals that the Mountain Pass …

Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong

Open Access Theses & Dissertations

I use updated gravity data, available aeromagnetic data, and other geophysical information as constraints to develop 2D and 3D structural models of density and magnetic susceptibility to better locate and determine the shape of the Border Ranges fault system (BRFS), the Border Range ultramafic and mafic assemblages and other forearc-arc boundary structures in south-central Alaska, that have previously been studied in only limited detail. There are three geophysical research projects that form the chapters of the dissertation. First, I estimated near-surface density variations in the central Kenai Peninsula based on the adaptation of the Nettleton (1939)-Parasnis (1952) method using Tarantola …

An Integrated Geophysical And Geologic Study Of The Paleogene-Age Volcanic Body And Possible Landslide Deposit On The South Slope Of The Traverse Mountains, Utah, John C. Hoopes

Theses and Dissertations

Development of homes, roads, and commercial buildings in northern Utah has grown significantly during the last several decades. Construction has expanded from the valley floor to higher elevations of benches, foothills, and other elevated regions of the Wasatch Mountain Front. Construction in the higher elevation areas are a concern due to potential for landslides, both new and reactivated. Landslides have been identified in this region and are dated as Pleistocene to historical in age. A possible landslide of about 0.5 km2 on the south slope of Traverse Mountain has been mapped by the Utah Geological Survey in 2005. Its surface …

Active Tectonics In Southern Alaska And The Role Of The Yakutat Block Constrained By Gps Measurements, Julie Elliott

Geosciences

GPS data from southern Alaska and the northern Canadian Cordillera have helped redefine the region's tectonic landscape. Instead of a comparatively simple interaction between the Pacific and North American plates, with relative motion accommodated on a single boundary fault, the margin is made up of a number of small blocks and deformation zones with relative motion distributed across a variety of structures. Much of this complexity can be attributed to the Yakutat block, an allochthonous terrane that has been colliding with southern Alaska since the Miocene. This thesis presents GPS data from across the region and uses it to constrain …

Geophysical Reconnaissance Of Karst Sinkhole Occurrences In Jeram, Kinta Valley, West Malaysia After The 2004 Indian Ocean Earthquake, R.F. Muhammad, O. Al-Kouri, R. Yassin, C.N. Lat

Research Publications (2011 to 2015)

Geophysical and geospatial reconnaissance of karst features associated with sinkholes has been carried out in Jeram, Perak, West Malaysia. A rapid increase of sinkholes occurrences were reported after the disastrous 26th Dec. 2004 earthquake in Sumatera. Over 45 sinkholes of various sizes occurred in a small area of the ex-mine land. Many cavities are present in the subsurface karst that is covered by thin layers of loose sands and clay materials. These cavities are thought to be pre-existing features that had been rapidly filled with sand/clay, due to the tremor triggered from the earthquake.

The Earthquake Cycle Of Strike-Slip Faults, Gina M. Schmalzle

Open Access Dissertations

An earthquake is a mechanism of stress release along plate boundaries due to relative motion between the Earth's lithospheric blocks. The period in which stresses are accruing across the plate boundary is known as the interseismic portion of the earthquake cycle. This dissertation focuses on interseismic portion of the earthquake cycle to extract characteristics of fault, shear zone and rock properties. Global Positioning System (GPS) data are used to observe the pattern of deformation across two primarily strike-slip fault systems: the Carrizo Segment of the San Andreas Fault (SAF) and the Eastern California Shear Zone (ECSZ). Two sets of GPS …

Investigating The Margins Of Pleistocene Lake Deposits With High-Resolution Seismic Reflection In Pilot Valley, Utah, John V. South

Theses and Dissertations

A vast area of the northeastern Great Basin of the western USA was inundated by a succession of Plio-Pleistocene lakes, including Lake Bonneville (28 ka to 12 ka). The Pilot Valley playa, located just east of the Utah-Nevada border near Wendover, Utah, within the eastern Basin and Range Province, represents an 8 to 16 km wide and ~50 km long remnant of these lakes. The playa corresponds to the upper surface of a closed basin that is delimited by two mountain ranges, which are mantled by recent alluvial fans over which the playa sediments have prograded. In order to investigate …

Temporal Variation Of Seismic B-Values Beneath Northeastern Japan Island Arc, Aimin Cao, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Analysis of a high quality seismic catalog reveals that the average of seismic b-values in the crust beneath most part of northeastern Japan island arc decreased from 0.86 between 1984 and 1990, to 0.73 between 1991 and 1995. The two areas with the largest decrease are found to be in the same areas where the coupling between the North American and the Pacific plates is the highest, as suggested by a recent geodetic study. In the same time period, the annual seismic moment release increased by 10 times. In addition, there seems to be a corresponding increase in volcanic activities …

Refined Kinematics Of The Eastern California Shear Zone From Gps Observations, 1993-1998, M. Meghan Miller, Timothy H. Dixon, Roy K. Dokka

All Faculty Scholarship for the College of the Sciences

Global Positioning System (GPS) results from networks spanning the Eastern California shear zone and adjacent Sierra Nevada block, occupied annually between 1993 and 1998, constrain plate margin kinematics. We use an elastic block model to relate GPS station velocities to long‐term fault slip rate estimates. The model accounts for elastic strain accumulation on the San Andreas fault, as well as faults of the Eastern California shear zone. South of the Garlock fault, 14 mm/yr of dextral shear is distributed across the Eastern California shear zone. Some of this slip penetrates eastward into the Basin and Range, and a collective budget …

Till Deformation Beneath Black Rapids Glacier, Alaska, And Its Implication On Glacier Motion, Martin Truffer

Theses (Unassigned)

The motion of a glacier is largely determined by the nature of its bed. The basal morphology and its reaction to the overlying ice mass have been subject to much speculation, because the glacier bed is usually difficult to access, and good field data are sparse. In spring 1997 a commercial wireline drill rig was set up on Black Rapids Glacier, Alaska, to extract cores of basal ice, subglacial till, and underlying bedrock. One of the boreholes was equipped with three tiltmeters to monitor till deformation, and a piezometer to record pore water pressure. The surface velocity and ice deformation …

Pattern And Process In Volcano Seismology, John Paul Benoit

Theses (Unassigned)

The patterns of occurrence and the underlying processes of two important seismological phenomena at volcanoes, earthquake swarms and volcanic tremor, were investigated. A global database of volcanic earthquake swarm parameters was compiled and was used to evaluate the March 10-14, 1996 seismo-volcanic crisis at Akutan Volcano, Alaska. Earthquake swarm durations and magnitudes were compared with eruptive activity using this database. Trends identified using the database suggest that the Akutan swarm was not precursory and, no eruption occurred. We postulate that a deep instrusion with a large opening component occurred under the flanks of Akutan. The global swarm database has provided …

Upper Crustal Structure Of Southern Alaska: An Interpretation Of Seismic Refraction Data From The Trans-Alaska Crustal Transect, Lorraine W. Wolf

Geosciences

Seismic refraction and wide-angle reflection data from the U.S. Geological Survey's Trans-Alaska Crustal Transect is used to investigate the upper crustal structure of southcentral Alaska. The data consist of two intersecting refraction lines: the 135-km Chugach profile which follows the E-W strike of the Chugach Mountains and the 126-km Cordova Peak profile which follows the N-S regional dip. The four shots of the Chugach profile and the five shots of the Cordova Peak profile were recorded on 120 portable seismic instruments spaced at 1-km intervals. Interpretation of data from the Chugach terrane indicates that near-surface unconsolidated sediment and glacial ice …

Paleomagnetism And Paleogeography Of Cretaceous Northern Alaska, William Karl Witte

Geosciences

No abstract provided.