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Calcite Cementation Of Sixty-Five-Year-Old Aragonite Sand Dredge Pile, Nathan M. Snyder 2011 University of Mississippi

Calcite Cementation Of Sixty-Five-Year-Old Aragonite Sand Dredge Pile, Nathan M. Snyder

Electronic Theses and Dissertations

Dredging of the harbor at Stocking Island, Bahamas (23°31'45"N, 75°49'41"W) in 1942 produced four dredge piles of cross-bedded aragonite skeletal sand. The spoils piles are on the leeward (western) shore of the island, where they are subject to minimal wave energy. Collectively they are 350 x 50 m in plan view and 2 m high. The surface is very well cemented, which requires a hammer and chisel for sampling. Samples were collected from six sites at various locations of the dredge pile. Samples were analyzed for both chemical and physical properties using thin-section examination, X-ray diffraction, X-ray fluorescence, bulk density …


A Gis Investigation Of Regional Geologic Controls On Mercury Deposits In The Southwest Region Of Arkansas, Lindsey Carol Langsdon 2011 University of Mississippi

A Gis Investigation Of Regional Geologic Controls On Mercury Deposits In The Southwest Region Of Arkansas, Lindsey Carol Langsdon

Electronic Theses and Dissertations

The mercury district of southwest Arkansas, located within Clark, Pike, and Howard counties, contains 77 mapped mercury deposits, primarily in the form of cinnabar, found within the sandstones and shales of the Stanley and Jackfork Formations. The geographic locations of the majority of the deposits tend to form an east-northeast alignment in map view. Utilization of Geographic Information Systems (GIS) tools provided insight to the regional controls on the spatial distribution of the mercury deposits by examining the proposed relationships between mercury deposits and regional faults or changes in lithology, both of which have been suggested (Clardy and Bush, 1976) …


Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province, Lamuail Bashir 2011 Missouri University of Science and Technology

Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province, Lamuail Bashir

Doctoral Dissertations

"Stacking of about 15,500 P-to-S receiver functions recorded at 72 USArray and other broadband seismic stations placed on the Colorado Plateau and the SBRP in Arizona revealed systematic spatial variations in crustal Vp/Vs, crustal thickness and amplitude of P-to-S converted phases. Our results reveal that the BRP is characterized by a thin crust (28.2 ± 0.5 km), a mean Vp/Vs of 1.761 ± 0.014 and a mean amplitude (R) of P - to - S converted wave (relative to that of the direct P wave) of 0.181 ± 0.014 that are similar to a typical continental crust, consistent with the …


Geology Of Cumberland Gap National Historical Park, Matthew M. Crawford, Hanna Hunsberger 2011 University of Kentucky

Geology Of Cumberland Gap National Historical Park, Matthew M. Crawford, Hanna Hunsberger

Map and Chart--KGS

Cumberland Gap National Historical Park is located in parts of Kentucky, Virginia, and Tennessee. The park was authorized by President Franklin Roosevelt on June 11, 1940, and is now the largest historical park in the National Park System. It contains 24,000 acres along Cumberland Mountain near Ewing, Va., proceeding southwest toward Fern Lake in Tennessee, a distance of approximately 20 miles. The average width of the park is only 1.6 miles.

The park hosts a distinctive range of geologic processes and features. Unique structural geology, caves and karst, surface and groundwater erosion, and mass wasting are just a few of …


Kentucky Landscapes Through Geologic Time, Daniel I. Carey 2011 University of Kentucky

Kentucky Landscapes Through Geologic Time, Daniel I. Carey

Map and Chart--KGS

We now understand that the earth’s crust is broken up into a number of plates, some of continental size, and that these plates have been moving— centimeters a year—throughout geologic history, driven by the internal heat of the earth. This movement creates our mountain chains, earthquakes, geologic faults, and volcanoes. The theory of plate tectonics (from the Greek, tektonikos: pertaining to building) attempts to describe the process and helps explain the geology of Kentucky.

The geologic story of the rocks that form Kentucky’s landscape began a half billion years ago when the area was covered by water. Deposits of sand, …


Distribution And Properties Of Vesicular Horizons In The Western United States, Judith K. Turk, Robert C. Graham 2011 University of California, Riverside

Distribution And Properties Of Vesicular Horizons In The Western United States, Judith K. Turk, Robert C. Graham

Conservation and Survey Division: Faculty and Staff Publications

Vesicular horizons are thin (usuallycm) surface or near-surface horizons characterized by the predominance of vesicular porosity. Th ey are widespread in arid and semiarid lands, occurring on every continent and covering 156,000 km2 of the western United States. Vesicular horizons have critical implications for management due to their role in controlling surface hydrology and dust mobilization. Th is study evaluates the distribution and varia-tion in expression of vesicular horizons across the western United States using the soil databases available from the USDA. A vesicular horizon index (VHI) that incorporates vesicular horizon thickness and the size and quantity of vesicular pores …


Stratigraphy And Petroleum Production Potential Of The Spearfish Formation In North Central North Dakota, Nnaemeka C. Anyanwu 2011 University of North Dakota

Stratigraphy And Petroleum Production Potential Of The Spearfish Formation In North Central North Dakota, Nnaemeka C. Anyanwu

Theses and Dissertations

The Spearfish oil play is unconventional requiring the use of horizontal wells that are fracture stimulated to deliver economic flow rates. However, fraccing into the underlying water has been a source of significant production problems for operators. The key to developing the area is to keep the individual fracs large enough to stimulate the tight Spearfish sands but not to let them propagate into the underlying water zone.

The Spearfish Formation of the Black Hills has been traced into the subsurface of the Williston Basin in western North Dakota from bore holes at the northern margin of the outcrop area …


Geomechanical Stability Analysis For Co2 Sequestration In Carbonate Formation, Xue J. Zhou 2011 University of North Dakota

Geomechanical Stability Analysis For Co2 Sequestration In Carbonate Formation, Xue J. Zhou

Theses and Dissertations

Geomechanical analysis is one of the fundamental pillars to build up the confidence of geological sequestration of CO2. Large scale CO2 sequestration in deep carbonate formation is a complicated geological process, which will non-reversibly transform the presumed equivalent and stable status of a sedimentary basin that formed over millions of years: chemically, hydraulically, geothermally, and geomechanically. In this dissertation, thermoporoelasticity guides the theoretical establishment of a conservative baseline for the geomechanical stability analysis of CO2 sequestration.

Extensive laboratory tests, including CO2 flooding tests, permeability tests, uniaxial and triaxial tests, Brazilian tensile strength tests, poroelasticity tests, point load tests, and fracture …


Chemical Evolution And Residence Time Of Groundwater In The Wilcox Aquifer Of The Northern Gulf Coastal Plain, Estifanos Haile 2011 University of Kentucky

Chemical Evolution And Residence Time Of Groundwater In The Wilcox Aquifer Of The Northern Gulf Coastal Plain, Estifanos Haile

Theses and Dissertations--Earth and Environmental Sciences

This study aims to integrate groundwater geochemistry and mathematical modeling to determine the dominant geochemical processes and groundwater residence time within the Wilcox aquifer in the northern Gulf Coastal Plain. Groundwater samples were collected and analyzed for major ion chemistry, stable isotopes (18O, 2H, and 13C), and radioisotope 36Cl content. Geochemical modeling enabled the identification of major sources and sinks of solutes in the aquifer. A two-dimensional, finite-difference, numerical model was used to determine the deep groundwater flow rate and transport of 36Cl in the aquifer. Major ion chemistry shows a chromatographic pattern along …


Arsenic Heterogeneity In Aquifer Sediments From West Bengal, India, Emily Eastridge 2011 University of Kentucky

Arsenic Heterogeneity In Aquifer Sediments From West Bengal, India, Emily Eastridge

Theses and Dissertations--Earth and Environmental Sciences

Multiple studies in the Bengal basin have shown that elevated As in groundwater coincides with reduced, relatively dark sediments of Himalayan provenance. In West Bengal state (India), As concentrations > 10 μg/L tend to occur east of the River Bhagirathi-Hoogly, the main distributary of the Ganges. Associations among sediment chemistry and mineralogy for four cores from either side of the Bhagirathi-Hoogly (cores 1 and 2 to the east, 3 and 4 to the west) in Murshidabad district were investigated. Ten sediment samples were collected from each boring at various depths to a maximum of 38 to 43 m. Sediment chemistry was …


Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya 2011 Texas A & M University - College Station

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …


Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin, Christopher D. Henry, Allen J. McGrew, Joseph P. Colgan, Arthur W. Snoke, Matthew E. Brueseke 2011 University of Nevada, Reno

Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin, Christopher D. Henry, Allen J. Mcgrew, Joseph P. Colgan, Arthur W. Snoke, Matthew E. Brueseke

Department of Earth, Environment and Sustainability Faculty Publications

This field trip examines contrasting lines of evidence bearing on the timing and structural style of Cenozoic (and perhaps late Mesozoic) extensional deformation in northeastern Nevada. Studies of metamorphic core complexes in this region report extension beginning in the early Cenozoic or even Late Cretaceous, peaking in the Eocene and Oligocene, and being largely over before the onset of “modern” Basin and Range extension in the middle Miocene. In contrast, studies based on low- temperature thermochronology and geologic mapping of Eocene and Miocene volcanic and sedimentary deposits report only minor, localized extension in the Eocene, no extension at all in …


'Sticky Spots' And Subglacial Lakes Under Ice Streams Of The Siple Coast, Antarctica, Olga V. Sergienko, Christina L. Hulbe 2011 Princeton University

'Sticky Spots' And Subglacial Lakes Under Ice Streams Of The Siple Coast, Antarctica, Olga V. Sergienko, Christina L. Hulbe

Geology Faculty Publications and Presentations

Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ice streams can be highly variable and that there can be widespread regions where basal traction is high. To seek an explanation for why lakes appear to be sited near areas with high basal traction, we use numerical models to simulate ice-stream dynamics, thermodynamics and subglacial water flow. We demonstrate that the ice flow over high basal traction …


Insights Into The 1968–1997 Dasht-E-Bayaz And Zirkuh Earthquake Sequences, Eastern Iran, From Calibrated Relocations, Insar And High-Resolution Satellite Imagery, R. T. Walker, E. A. Bergman, Walter Szeliga, E. J. Fielding 2011 University of Oxford

Insights Into The 1968–1997 Dasht-E-Bayaz And Zirkuh Earthquake Sequences, Eastern Iran, From Calibrated Relocations, Insar And High-Resolution Satellite Imagery, R. T. Walker, E. A. Bergman, Walter Szeliga, E. J. Fielding

Faculty Scholarship for the Cascadia Hazards Institute

The sequence of seismicity in the Dasht-e-Bayaz and Zirkuh region of northeastern Iran, which includes 11 destructive earthquakes within a period of only 30 years, forms one of the most outstanding examples of clustered large and intermediate-magnitude seismic activity in the world.We perform a multiple-event relocation analysis, with procedures to remove systematic location bias, of 169 earthquakes, most of which occurred in the period 1968–2008, to better image the distribution of seismicity within this highly active part of Iran. The geographic locations of the clustered earthquakes were calibrated by the inclusion of phase arrivals from seismic stations at short epicentral …


Evolution Of The Veternica Cave (Medvednica Mountain, Croatia) Drainage System: Insights From The Distribution And Dating Of Cave Deposits, Damir Lacković, Bosiljka Glumac, Yemane Asmerom, Andrej Stroj 2011 Croatian Natural History Museum

Evolution Of The Veternica Cave (Medvednica Mountain, Croatia) Drainage System: Insights From The Distribution And Dating Of Cave Deposits, Damir Lacković, Bosiljka Glumac, Yemane Asmerom, Andrej Stroj

Geosciences: Faculty Publications

Detailed field examination, U-Th age dating, and stable isotope analysis of Veternica flowstone and shelfstone deposits have been employed in order to unravel details about the geological history of Veternica Cave (Medvednica Mountain, Croatia). The study was carried out in the hydrologically inactive part of the main cave channel, which is developed mainly along the unconformity between Triassic dolostone and Miocene limestone. For 180 m from the cave entrance, (located at 320 metres above sea level (asl)), the morphology of the main channel reflects exclusively phreatic conditions in the cave until the end of its hydrological activity. From 180 to …


Volcanism And Astrobiology: Life On Earth And Beyond, Charles S. Cockell, Sherry L. Cady, Nicola McLoughlin 2011 University of Edinburgh

Volcanism And Astrobiology: Life On Earth And Beyond, Charles S. Cockell, Sherry L. Cady, Nicola Mcloughlin

Geology Faculty Publications and Presentations

Editorial Introduction to the 2011 Special Issue of Astrobiology.


A 1-D Mechanistic Model For The Evolution Of Earthflow-Prone Hillslopes, Adam M. Booth, Joshua J. Roering 2011 Portland State University

A 1-D Mechanistic Model For The Evolution Of Earthflow-Prone Hillslopes, Adam M. Booth, Joshua J. Roering

Geology Faculty Publications and Presentations

In mountainous terrain, deep‐seated landslides transport large volumes of material on hillslopes, exerting a dominant control on erosion rates and landscape form. Here, we develop a mathematical landscape evolution model to explore interactions between deep‐seated earthflows, soil creep, and gully processes at the drainage basin scale over geomorphically relevant (>103 year) timescales. In the model, sediment flux or incision laws for these three geomorphic processes combine to determine the morphology of actively uplifting and eroding steady state topographic profiles. We apply the model to three sites, one in the Gabilan Mesa, California, with no earthflow activity, and two …


Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton 2011 University of Kentucky

Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton

University of Kentucky Master's Theses

Currently, bacterial movement in karst aquifers is not well understood. Use of stable isotopes to label non-pathogenic Escherichia coli as a particulate groundwater tracer in karst systems has been examined in previous studies. Loss of the stable isotope signal is anticipated in traces greater than 500 m in length. Potential loss of 15N due to predation by protozoa was examined. Filter-sterilized water from Royal Spring in Georgetown, Kentucky, was inoculated with a mixture of either Tetrahymena pyriformis or Colpoda steinii and 15N-enriched E. coli and stored in the dark at 14°C. Samples were analyzed for their nitrogen isotope …


Provenance Signature Of A Forearc Basin Modified By Spreading Ridge Subduction: Detrital Zircon Geochronology And Detrital Modes From The Paleogene Arkose Ridge Formation, Southern Alaska, Cullen Kortyna 2011 Bucknell University

Provenance Signature Of A Forearc Basin Modified By Spreading Ridge Subduction: Detrital Zircon Geochronology And Detrital Modes From The Paleogene Arkose Ridge Formation, Southern Alaska, Cullen Kortyna

Honors Theses

Upper Paleocene–Eocene boulder conglomerate, cross-stratified sandstone, and laminated carbonaceous mudstone of the Arkose Ridge Formation exposed in the southern Talkeetna Mountains record fluvial-lacustrine deposition proximal to the volcanic arc in a forearc basin modified by Paleogene spreading ridge subduction beneath southern Alaska. U-Pb ages of detrital zircon grains and modal analyses were obtained from stratigraphic sections spanning the 2,000 m thick Arkose Ridge Formation in order to constrain the lithology, age, and location of sediment sources that provided detritus. Detrital modes from 24 conglomerate beds and 54 sandstone thin sections aredominated by plutonic and volcanic clasts and plagioclase feldspar with …


Applied Palynology: Multidisciplinary Case Studies From Egypt, Gulf Of Mexico And Usa, Mohamed K. Zobaa 2011 Missouri University of Science and Technology

Applied Palynology: Multidisciplinary Case Studies From Egypt, Gulf Of Mexico And Usa, Mohamed K. Zobaa

Doctoral Dissertations

"Various applications of palynology have been used to study case studies from four different parts of the world, namely northern Egypt, offshore Gulf of Mexico, eastern Tennessee (USA), and New Orleans, Louisiana (USA). In these case studies, palynomorphs (spores, pollen, dinoflagellate cysts, and algae) have been utilized to define zones of hydrocarbon potential, reconstruct paleoenvironmental and paleoclimatic conditions, constrain the ages of the studied rock sequences, and express its potential as a replacement proxy for some expensive organic geochemical analyses. The ability to detect past hurricane activities and their associated damage to the geologic record is here presented as a …


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