Geology Commons^™

Thermobarometry Of Metamorphosed Pseudotachylyte And Determination Of Seismic Rupture Depth During Devonian Caledonian Extension, North Norway, Susan E. Leib

Theses and Dissertations--Earth and Environmental Sciences

Crustal faulting has long been known as the source of shallow seismicity, and the seismogenic zone is the depth (3-15 km) within the crust that is capable of co-seismic slip, largely under brittle conditions. However, some continental seismicity occurs at depths >> 15 km. I performed thermobarometry of mylonitic pseudotachylyte to determine the P-T of a seismogenic extensional fault in the Caledonian Norwegian margin. Two shear zones (Eidsfjord and Fiskfjord) located in northern Norway exhibit brittle extension propagating into the ductile regime of the lower crust as evidenced by the presence of pseudotachylyte. Averages from Eidsfjord (653 ± 38°C and 570 …

Spatio-Temporal Variability In Groundwater Discharge And Contaminant Fluxes Along A Channelized Stream In Western Kentucky, Ganesh N. Tripathi

Theses and Dissertations--Earth and Environmental Sciences

Spatio-temporal variability in groundwater discharge and contaminant fluxes along a channelized stream in western Kentucky

Surface and groundwater discharges and contaminant fluxes can vary with time and space depending upon the hydrogeological processes and geological setting of the area of interest. This study examined a ~300-m-long, channelized reach of a first-order perennial stream, Little Bayou Creek, in the Coastal Plain of far western Kentucky during the period October 2010–February 2012. Along the study reach, springs discharge groundwater contaminated by the chlorinated organic compound trichloroethene (TCE) and radionuclide technetium-99 (⁹⁹Tc) released as a result of past activities at the …

Physical And Sequence Stratigraphy Of The Late Cretaceous Chispa Summit Formation, Jeff Davis County, Texas, Patrick Thomas Dietzel

Open Access Theses & Dissertations

The Late Cretaceous Chispa Summit Formation of west Texas has historically been of interest to the petroleum industry; with new technologies, this old, uneconomical play could prove significant, if not for energy resources, for educational purposes, but little work has been conducted on the formation. The Eagle Ford Formation of southern Texas is time equivalent to the Chispa Summit Formation and is a highly prolific hydrocarbon resource.

Located in western Jeff Davis County, Texas, the Chispa Summit Formation consists of marine shales interbedded with limestone beds and sporadically located siliciclastic beds, measuring a total of 610 m at the type …

Pliocene Sinistral Slip Across The Adobe Hills, Eastern California-Western Nevada: Kinematics Of Fault Slip Transfer Across The Mina Deflection, Sarah Nagorsen-Rinke, Jeffrey Lee, Andrew Calvert

All Faculty Scholarship for the College of the Sciences

The Adobe Hills region (California and Nevada, USA) is a faulted volcanic field located within the western Mina deflection, a right-stepping zone of faults that connects the northern Eastern California shear zone (ECSZ) to the south with the Walker Lane belt (WLB) to the north. New detailed geologic mapping, structural studies, and ⁴⁰Ar/³⁹Ar geochronology in the Adobe Hills allow us to calculate fault slip rates and test predictions for the kinematics of fault slip transfer into the Mina deflection. The Adobe Hills are dominated by Pliocene tuffaceous sandstone, basaltic lavas that yield ⁴⁰Ar/³⁹Ar ages …

Controlling Factors On Bedrock River Sinuosity In The Eastern Tibetan Plateau, Lydia Curliss

Honors Papers

Average sinuosity of bedrock rivers across the eastern Tibetan Plateau (including the Yangtze, Mekong, Salween, Irrawaddy, and Tsang Po) ranges from 1.20-1.41. From 25°-30°N, sinuosity marginally increases east to west; over the entire distance of each river, sinuosity increases north to south. Increases in sinuosity parallel a regional tectonic gradient in an area with a marginal climate gradient. Several past studies correlate sinuous bedrock rivers in mountainous regions with gradients in climate, arguing that landslides are the main mechanism by which bedrock rivers increase sinuosity. Other studies find correlations between tectonics and increasing landslide frequency. To investigate the role of …

Thermobarometric Modeling Of The Catalina Amphibolite Unit: Implications For Tectonic And Metasomatic Models, Henry W. Towbin

Honors Papers

On Santa Catalina Island, Ca high-grade amphibolite units overlie progressively lower- grade blueschist units in an inverted stack structure. This juxtaposition of high grade and low-grade metamorphic units has long been the subject of much debate as to the tectonic origins of the formation and how it relates to California's tectonic evolution. Previous petrography and thermobaromety of blocks in the amphibolite unit estimate pressures and temperatures of ~8-11 kbar and ~640-750 °C (Platt, 1975; Sorensen and Barton 1987). These estimates were calculated before many of the computational advances in modern thermobarometry. Using Equilibrium Assemblage Diagrams (EAD) calculated with Theriak Domino, …

Characterization Of Mass Wasting Through The Spectral Analysis Of Lidar Imagery: Owyhee River, Southeastern Oregon, Christopher Earl Markley

All Master's Theses

Quantifying landslide character is an important aspect of understanding hillslope-channel interactions. Spectral analysis of high-resolution, LiDAR derived, DEMs was carried out following methods described by Booth et al. (2009) to determine the characteristic spectral signature inherent in different styles of landslides in the Owyhee River Canyon in southeastern Oregon. The main factor in landslide generation in this location is a lithologic contact in which a coherent basaltic caprock overlies relatively weak sediments where most of the landslide failure surfaces originated. Changes in spectral power distribution through time were quantified by comparing a sequence of adjacent rotational landslides of apparent different …

Short And Long Term Volcano Instability Studies At Concepción Volcano, Nicaragua, Jose Armando Saballos

USF Tampa Graduate Theses and Dissertations

Concepción is the most active composite volcano in Nicaragua, and is located on Ometepe Island, within Lake Nicaragua. Moderate to small volcanic explosions with a volcanic explosivity index (VEI) of 1-2 have been characteristic of this volcano during the last four decades. Although its current activity is not violent, its volcanic deposits reveal stages of violent activity involving Plinian and sub-Plinian eruptions that deposited vast amounts of volcanic tephra in the Atlantic Ocean. These observations, together with the 31,000 people living on the island, make Concepción volcano an important target for volcanological research.

My research focuses on the investigation of …

Morphological Changes Associated With Tropical Storm Debby In The Vicinity Of Two Tidal Inlets, John's Pass And Blind Pass, West-Central Florida, Andrew Brownell

USF Tampa Graduate Theses and Dissertations

Tropical Storm Debby affected the Gulf coast of Florida in late June, 2012. The storm's southerly approach temporarily reversed the annual net southward longshore sediment transport. The energetic conditions associated with Tropical Storm Debby can be seen in the wind, wave and tidal measurements taken from both onshore and offshore weather stations around the dual tidal inlets system of John's Pass and Blind Pass, approximately 25 kilometers north of the mouth of Tampa Bay. The energetic and persistent southerly forcing, in addition to higher storm induced water levels and wave heights, resulted in atypical beach erosion and sediment deposition on …

Distinguishing Processes That Induce Temporal Beach Profile Changes Using Principal Component Analysis: A Case Study At Long Key, West-Central Florida, Denise Marie Davis

USF Tampa Graduate Theses and Dissertations

The heavily developed Long Key is located in Pinellas County in west-central Florida. The structured Blind Pass at the north end of the barrier island interrupts the southward longshore sediment transport, resulting in severe and chronic beach erosion along the northern portion of the island. Frequent beach nourishments were conducted to mitigate the erosion. In this study, the performance of the most recent beach nourishment in 2010 is quantified through time-series beach profile surveys. Over the 34-month period, the nourished northern portion of the island, Upham Beach, lost up to 330 m3/m of sand, with a landward shoreline retreat of …

Hypogene Speleogenesis In The Cerna River Basin, Sw Romania: A Sedimentological, Mineralogical, And Stable Isotopic Approach, Cristina Montana Puscas

USF Tampa Graduate Theses and Dissertations

Ever since it was identified as a speleogenetic process in the Guadalupe Mountains of New Mexico, USA, hypogene speleogenesis has become the focus of numerous research projects aimed at discerning between classical epigene caves and sulfuric acid or thermal caves. The first distinguishing characteristics that were recognized for hypogene caves were passage and cave morphology. The following step was the identification of rare minerals, specific for processes associated to hypogene speleogenesis. One other important step was the recognition of the importance of stable isotopes - mainly of S - in tracing the source of S and the chemical processes affecting …

Stable Isotopes And Trace Elements In Tooth Enamel Bioapatite: Effects Of Diagenesis And Pretreatment On Primary Paleoecological Information, Jessica Norman Wilson

USF Tampa Graduate Theses and Dissertations

The geochemical analysis of bioapatite in vertebrate skeletal tissues is an important tool used to obtain ecological information from fossil animals. An important consideration when conducting stable isotope and trace element analyses is obtaining biogenic information that has been unaffected by diagenetic processes.

A two-step pretreatment procedure is commonly used remove diagenetically altered material by removing organic material, via an oxidation reaction with H2O2 or NaOCl, and secondary carbonate, via dissolution in dilute acetic acid, from bioapatite. While much work has been done to determine the efficacy of the pretreatment process, little research has been conducted to determine the potential …

A Study Of The Impacts Of Freeze-Thaw On Cliff Recession At The Calvert Cliffs In Calvert County, Maryland, Bonnie Elizabeth Zwissler

Dissertations, Master's Theses and Master's Reports - Open

The Calvert Cliffs, which form much of the western coastline of the Chesapeake Bay in Calvert County, Maryland, are actively eroding and destabilizing, resulting in a critical situation for many homes in close proximity to the slope's crest. Past studies have identified that where waves directly interact with the toe of the slope, wave action controls cliff recession; however, where waves do not regularly interact with the slope toe, the past work identified that freeze-thaw controls recession. This study investigated the validity of this second claim by analyzing the recession rate and freeze-thaw behavior of six study sites along the …

Trophic State Monitoring Of Lakes And Reservoirs Using Remote Sensing, Michelle Aten

Electronic Theses and Dissertations

Lakes and reservoirs are important resources that provide water for critical needs, such as drinking water, agriculture, recreation, fisheries, wildlife, and other uses. However, there is increasing concern that anthropogenic eutrophication threatens the usability of these natural resources. Therefore, this research investigates these complex hydrologic ecosystems and recommends a methodology for monitoring the trophic state of lakes and reservoirs using remote sensing data. The Mississippi Department of Environmental Quality provided in situ data for seven Mississippi lakes including, Arkabutla, Bay Springs, Enid, Grenada, Okatibbee, Ross Barnett, and Sardis lakes. This research explored the relationships between the Secchi depth (SD), chlorophyll-a …

Appendix C—Deformation Models For Ucerf3, Tom Parsons, Kaj M. Johnson, Peter Bird, Jayne Bormann, Timothy E. Dawson, Edward H. Field, William C. Hammond, Thomas A. Herring, Robert Mccaffrey, Zheng-Kang Shen, Wayne R. Thatcher, Ray J. Weldon Ii, Yuehua Zeng

Geology Faculty Publications and Presentations

This document describes efforts to best characterize seismogenic deformation in and near California. The rate of hazardous earthquakes in California is expected to be proportional to deformation rates; in particular, the rates at which faults slip. Fault slip rates are determined from offsets of geologic and geomorphic features of measured age and by modeling geodetically determined surface displacement rates. Extensive use of geodesy in the form of Global Positioning System (GPS) observations is a new feature brought into the Working Group on California Earthquake Probabilities (WGCEP) forecasts for the Uniform California Earthquake Rupture Forecast, version 3 (UCERF3) model. Geodetic measurements …

Saturated Thickness Of The Unconfined Portions Of The High Plains Aquifer, Conservation And Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

The Groundwater Atlas Of Nebraska, Jesse T. Korus, Leslie M. Howard, Aaron R. Young, Dana P. Divine, Mark E. Burbach, J. Michael Jess, Douglas R. Hallum, R.F. Diffendal, Jr., R.M. Joeckel

Conservation and Survey Division: Faculty and Staff Publications

Groundwater has long been important to inhabitants of Nebraska. Native Americans in the Great Plains erected their villages near water sources. Early explorers from Europe and pioneers heading west following river valleys depended on ample freshwater in the Nebraska Territory for drinking water and livestock supplies. These Europeans, however, considered the Nebraska Territory part of “The Great American Desert” and few people had an idea of the vast groundwater resource in Nebraska.

Nebraska Statewide Groundwater-Level Monitoring Report 2013, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly

United States Geological Survey: Staff Publications

Although numerous studies have attempted to place species of interest within the context of food webs, such efforts have generally occurred at small scales or disregard potentially important spatial heterogeneity. If food web approaches are to be employed to manage species, studies are needed that evaluate the multiple habitats and associated webs of interactions in which these species participate. Here, we quantify the food webs that sustain rearing salmon and steelhead within a floodplain landscape of the Methow River, Washington, USA, a location where restoration has been proposed to restore side channels in an attempt to recover anadromous fishes. We …

Predictive Models For Escherichia Coli Concentrations At Inland Lake Beaches And Relationship Of Model Variables To Pathogen Detection, Donna S. Francy, Erin A. Stelzer, Joseph W. Duris, Amie M. G. Brady, John H. Harrison, Heather E. Johnson, Michael W. Ware

United States Geological Survey: Staff Publications

Predictive models, based on environmental and water quality variables, have been used to improve the timeliness and accuracy of recreational water quality assessments, but their effectiveness has not been studied in inland waters. Sampling at eight inland recreational lakes in Ohio was done in order to investigate using predictive models for Escherichia coli and to understand the links between E. coli concentrations, predictive variables, and pathogens. Based upon results from 21 beach sites, models were developed for 13 sites, and the most predictive variables were rainfall, wind direction and speed, turbidity, and water temperature. Models were not developed at sites …