Physical Sciences and Mathematics Commons^™

Fault-Adjacent Damage At The Base Of The Seismogenic Zone And Seismic Anisotropy Of Fold Structures, Won Joon Song

Electronic Theses and Dissertations

While earthquakes represent a major hazard to life and property, there are a number of open questions about how earthquake faults operate at depth, and how the energy released by earthquakes travels as elastic waves through Earth’s complexly deformed crustal rocks. The aims of my dissertation are to explore (a) the extent of co-seismic damage in an ancient earthquake fault exhumed from great depths, (b) the deformation processes and mechanics of the fault at depth during earthquake cycles, and (c) the role of different rock structures in determining the velocities of seismic waves.

When tectonic plates collide, deformation tends to …

Hardbottom Characterization And Relationship To The Geologic Framework In Long Bay, South Carolina, Cathryn J. Wheaton

Electronic Theses and Dissertations

Hardbottom seafloor is a common element among sediment-starved portions of the inner continental shelf along the U.S. Atlantic margin. These areas are characterized by indurated sediment surfaces that are heavily altered by biological and physical processes. Long Bay, in northeastern South Carolina, offers ideal environmental conditions for hardbottom exposure with only patchy Holocene sand deposits, interspersed with extensive hardbottom areas. Here we use high-resolution multibeam bathymetry, CHIRP subbottom profiling and electrical resistivity data, along with surficial sediment samples, hardbottom thin sections, and water column radioisotope (radon-222) analysis to investigate the origin and geologic framework of a region of hardbottom seafloor …

A Geophysical Delineation Of A Normal Fault Within The Gulf Coastal Plain, Montgomery County, Texas, Danielle Minteer

Electronic Theses and Dissertations

The Gulf Coast of Texas has been a known hydrocarbon basin for many years with various structural trapping mechanisms such as anticlines, faults and salt domes. While most large salt domes have been extensively studied in the Gulf Coastal Plain, many smaller normal faults have not been studied in detail. This research study employs an integrated geophysical approach to mapping the Big Barn fault in Montgomery County, Texas. This fault is located on the Gulf Coastal Plain and is approximately 20 miles north of Houston, Texas. Most normal faults in the Gulf Coastal Plain formed as a result of the …

Utilizing Ground-Penetrating Radar In The Delineation And Cultural Resource Management Of Eroding Maine Coastal Shell Middens, Jacquelynn F. Miller

Electronic Theses and Dissertations

Shell middens along the Maine coast archive up to 5000 years of cultural and climatic change, but the record is continually and rapidly lost to the sea through climate-driven coastal erosion and sea-level rise. These sites were constructed by the ancestors of Maine Tribes, and are composed of centimeters to meters of clam (Mya arenaria) and/or oyster (Crassostrea virginica) shells, other faunal remains, and cultural materials. Shell middens record human interaction with the environment and early coastal occupation and adaptation. The faunal remains reflect paleoenvironmental conditions and the distribution of extinct and extant forage-species along the western Gulf of Maine. …

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) …