Physical Sciences and Mathematics Commons^™

Assessing The Relative Mobility Of Submarine Landslides From Deposit Morphology And Physical Properties: An Example From Kumano Basin, Nankai Trough, Offshore Japan, Zachary T. Moore

Theses and Dissertations--Earth and Environmental Sciences

A prominent landslide deposit in the Slope Basin seaward of the Megasplay Fault in the Nankai Trough was emplaced by a high-mobility landslide based on analysis of physical properties and seismic geomorphology. Slide acceleration is a critical variable that determines amplitude of slide-generated tsunami but is many times a variable with large uncertainty. In recent controlled laboratory experiments, the ratio of the shear stress to yield strength (defined as the Flow Factor) controls a wide spectrum of mass movement styles from slow, retrogressive failure to rapid, liquefied flows. Here, we apply this laboratory Flow Factor approach to a natural landslide …

Finding Mars Paleopoles From Magnetization Edge Effects To Determine The History Of Mars’ Core Dynamo, Melissa Lynn Ditty

Theses and Dissertations--Earth and Environmental Sciences

This is a new method of determining magnetization strength, direction, and paleopole location from magnetic anomalies across edges of the equatorial band of magnetic sources on Mars. Different assumed locations of paleopoles result in different inducing field directions in the vicinity of an edge. Thus, with different paleopoles, the resulting magnetic fields from the edges of magnetic sources are different, and correlate differently with the observed fields. Best correlating observed and computed magnetic edge effect fields yield the potential paleopoles. The total gradient (TG) of the z-component magnetic field was used to identify the edges of magnetization boundaries. Three edge …

Bedrock Geologic Mapping And Structural Analysis Of The Western Half Of The Petersham Quadrangle, Central Massachusetts: Further Tests Of The Model For Middle To Late Paleozoic Ductile Transpression, Vertical Extrusion, And Lateral Escape In The Northern Appalachians, Lucas P. Rohrer

Theses and Dissertations--Earth and Environmental Sciences

Bedrock mapping, structural analysis, and geochronology reveal the distribution of lithologies and timing of metamorphism and deformation in the western half of the Petersham 7.5’ quadrangle, western Massachusetts. Underlying lithologies are: (from west to east) the Ordovician Monson granitic orthogneiss, Silurian Rangeley migmatitic paragneiss, and Late Devonian (357 Ma) Hardwick tonalitic orthogneiss. Their tightly folded contacts strike north to south. The 361 Ma, unfoliated, strike-parallel Nichewaug quartz-diorite (10-100 m wide) intrusion spans the map area within the Rangeley. Evidence for vertical and lateral extrusion/escape of the Monson orthogneiss, as observed in the Palmer MA area, is absent. Instead, petrofabrics (foliations …

The Environmental Effects Of Coal Fires, Trent Garrison

Theses and Dissertations--Earth and Environmental Sciences

There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in …

Fluvial Responses To Growth Faulting In The West Pearl River, Louisiana, Stephen A. Prosser

Theses and Dissertations--Earth and Environmental Sciences

The Pearl River Delta (PRD) in southeastern Louisiana is an actively deforming deltaic complex displaying surface and near-surface evidence of growth faulting. Active growth faults in these environments are rarely identified at the surface, in part because the downthrown blocks often experience increased rates of sediment deposition leading to an obscured and low-relief, or entirely absent, surface expression. Faulting can be expressed in fluvial systems as changes in channel gradient, which often result in coincident changes in channel sinuosity, migration rates, planform deflections, and/or ponding features within the deformed zone. The study area is focused on a meander bend of …

Dynamic Surface Water-Groundwater Exchange In Tidal Freshwater Zones: Insights From The Christina River Basin (Delaware, Usa), Cole T. Musial

Theses and Dissertations--Earth and Environmental Sciences

In coastal rivers, tides can propagate for tens to hundreds of kilometers inland beyond the saltwater line. Yet the influence of tides on river-aquifer connectivity and solute transport in tidal freshwater zones (TFZs) is largely unknown. We estimate that along the TFZ of White Clay Creek (Delaware, USA), more than 17% of river water exchanges through hyporheic and riparian storage zones due to tidal pumping alone. Additional hyporheic processes such as flow through bedforms likely contribute even more exchange. The turnover length associated with the tidal pumping process is 39 km, similar to turnover lengths for all hyporheic exchange processes …

Subsurface Geological Analyses Of The Berea Petroleum System In Eastern Kentucky, Julie Floyd

Theses and Dissertations--Earth and Environmental Sciences

The Berea Sandstone is a Late Devonian, tight oil and gas reservoir that intertongues with the Bedford Shale in eastern Kentucky. In order to evaluate the Bedford-Berea interval in the subsurface, 555 well logs from the Kentucky Geological Survey’s oil and gas database were used to construct structure maps, isopach maps, and cross sections of the interval and its possible hydrocarbon source rocks. Gamma-ray logs were compared to known cores in order to separate Bedford from Berea lithologies. Maps and cross sections were compared to known basement structures to evaluate possible structural influences on the interval.

The Bedford-Berea interval is …