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Earth Sciences

Theses/Dissertations

1993

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A Study Of Aquifer Sensitivity And Vulnerability In Kalamazoo County, Michigan Based On Hydrogeologic And Agricultural Factors, Steven Douglas Chidester Dec 1993

A Study Of Aquifer Sensitivity And Vulnerability In Kalamazoo County, Michigan Based On Hydrogeologic And Agricultural Factors, Steven Douglas Chidester

Masters Theses

Groundwater in Kalamazoo County, Michigan has been impacted by human activities. This study presents a statistical method for predicting aquifer sensitivity/vulnerability within a glacio-hydrogeologic system.

Computerized data including 3620 water well records with partial chemical analyses, soil surveys, land use maps, and hydrogeologic reports were used to quantify aquifer parameters, nitrate-N contaminant concentrations, soil factors, and agricultural practices. Statistical analyses included simple t-tests , correlation, ANOV A, and multiple regression analyses.

The results indicate that there are statistically significant relationships between nitrate-N concentrations and depth of well submergence, well depth, clay thickness, partial clay thickness, land use, and soil slope. …


Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair Dec 1993

Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair

Morehead State Theses and Dissertations

1993 Fall Semester Senior Theses for the class Physical Science 471:

Petrologic Classification of Igneous and Metamorphic Rocks by Frank Baldridge

X -Ray Analysis of Cave Sediments From Pigeon Water Cave of Northeastern Pine Mountain by Billy B. Stapleton

The Correlation of Stream-deposited Breccias In Bat Cave, Carter Caves, Kentucky by James Bond

Jointing and Faulting in Selected Areas of Eastern Kentucky by Mark A. Blair


Spectral Analysis Of The Flow Behavior Of Big Spring, Kings Canyon National Park, California, Linda Urzendowski Dec 1993

Spectral Analysis Of The Flow Behavior Of Big Spring, Kings Canyon National Park, California, Linda Urzendowski

UNLV Theses, Dissertations, Professional Papers, and Capstones

Big Spring, the resurgence of a karst aquifer in the Lilburn Cave system (Kings Canyon National Park, California), displays the uncommon phenomena of ebb and flow discharge during periods of high runoff.

Hydrograph analyses indicate that the portion of Lilburn Cave between the Z-Room and Big Spring is primarily a conduit flow aquifer. The power spectra strongly indicate a nonlinear system, with evidence of quasi-linear behavior found on a smaller scale. The transfer and kernel function indicate that no additional significant inputs or outputs to the system exist. The bench-scale model built to simulate the ebb and flow cycles in …


The Geology Of The Tuff Of Bridge Spring: Southern Nevada And Northwestern Arizona, Shirley Ann Morikawa Dec 1993

The Geology Of The Tuff Of Bridge Spring: Southern Nevada And Northwestern Arizona, Shirley Ann Morikawa

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Tuff of Bridge Spring (TBS) is a regionally-widespread, andesite to rhyolite (59.50 to 74.91 wt. %) ash-flow tuff of mid-Miocene age (ca. 15.2 Ma) that is exposed in the northern Colorado River extensional corridor of southern Nevada and northwestern Arizona. Determination of the areal distribution, geochronology, lithology, geochemistry, and internal stratigraphy of the TBS is important for its establishment as a reliable stratigraphic reference horizon for tectonic reconstructions of the extensional corridor during the middle Miocene. Based on reoccurring patterns of major and trace element variation, the TBS is divided into constant Cr/variable SiO2 and variable Cr/variable SiO …


Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna Oct 1993

Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna

Chemistry & Biochemistry Theses & Dissertations

Sediments from different parts of the Chesapeake Bay were analyzed to determine the presence of volatile amines. A HF-HCl extraction method was used to extract both exchangeable and fixed amines from the sediments and a purge-and-trap technique was used to concentrate the amines. Following derivatization with heptafluorobutyric anhydride (HFBA), the HFBA-amines were analyzed by gas chromatography with electron capture detection and with mass spectrometric detection. One primary amine, i-amylamine with a concentration ranging from 0. 78 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty seven samples collected on three different dates in 1993. Another primary amine, 2-methylbutylamine with a concentration ranging from 0.18 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty three samples collected on three different dates in 1993. A secondary amine, diethylamine was detected but could not be quantified in a total of seven samples collected in September 1993. The concentrations of these amines varied with location in the Bay, depth in the sediment, and time of year the sediments were collected. The origin of i-amylamine and 2-methylbutylamine might be from the biological decarboxylation of amino acids leucine and isoleucine, respectively. The origin of diethylamine is unknown.


Depositional History, Sequence Stratigraphy And Diagenesis Of The Maryville Limestone (Middle Cambrian) Southern Appalachians, Krishnan Srinivasan Aug 1993

Depositional History, Sequence Stratigraphy And Diagenesis Of The Maryville Limestone (Middle Cambrian) Southern Appalachians, Krishnan Srinivasan

Doctoral Dissertations

The Conasauga Group constitutes part of a thick pericratonic Cambro-Ordovician passive-margin sequence along the eastern North American continent. The Cambrian carbonate platform was flanked by a high-relief shelf margin towards the east, facing the open ocean, while to the west the carbonate platform sloped into an intrashelf basin. It is this western shelf margin that is the topic of the present study. Detailed lithofacies analysis of the Middle Cambrian Maryville Limestone along a shelf-to-basin depositional transect reveals that the shelf evolved from a gently basinward sloping ramp to a rimmed platform fringed with steeper slopes. Cyanobacterial buildups (Renalcis-Girvanella) …


Precipitation Dynamics In Kalamazoo, Sw Michigan: A Stable Isotope Perspective, Madhav V. Machavaram Aug 1993

Precipitation Dynamics In Kalamazoo, Sw Michigan: A Stable Isotope Perspective, Madhav V. Machavaram

Masters Theses

No abstract provided.


Carbonate Platform Response To Tectonism And Eustasy: The Middle Cambrian Carbonates Of The Lower And Middle Conasauga Group, East Tennessee, Eugene Carlton Rankey Aug 1993

Carbonate Platform Response To Tectonism And Eustasy: The Middle Cambrian Carbonates Of The Lower And Middle Conasauga Group, East Tennessee, Eugene Carlton Rankey

Masters Theses

The Middle Cambrian Craig Limestone Member (Rogersville Shale) and Maryville Limestone are part of the thick Cambro-Ordovician pericratonic sedimentary package exposed in the Valley and Ridge province in East Tennessee. Exposures in the Dumplin Valley fault zone provide further details concerning the origin and development of these limestone formations.

Description of five sections, analysis of 125 thin sections and 98 slabs, and regional reconnaisance in the Dumplin Valley area reveal that the Craig Limestone Member represents "premature" demise of a carbonate shelf in that it did not develop as fully as the Maryville shelf and had no rimmed edge or …


Holocene And Modern Geomorphic Response To Forest Fires And Climate Change In Yellowstone National Park, Grant A. Meyer Jul 1993

Holocene And Modern Geomorphic Response To Forest Fires And Climate Change In Yellowstone National Park, Grant A. Meyer

Earth and Planetary Sciences ETDs

The Yellowstone fires of 1988 provided an opportunity to observe the geomorphic impact of widespread, intense forest fires on a mountain environment. Post-1988 fire-related sedimentation events also served as geomorphological and sedimentological analogs which were used to interpret a Holocene stratigraphic record of fire-related alluvial activity. Research focussed primarily on the steep-walled glacial trough valley of Soda Butte Creek, and parts of the Slough Creek and Lamar River drainages in northeastern Yellowstone.

All of the examined major post-1988 fire-related sedimentation events involved the generation of widespread surface runoff from brief, intense summer convective-storm precipitation on steep slopes in intensely burned …


The Biogeochemistry Of Iodine In Seawater, Lingsu Zhang Jul 1993

The Biogeochemistry Of Iodine In Seawater, Lingsu Zhang

OES Theses and Dissertations

Iodate and iodide are the two major species of iodine in seawater. In comparison to iodate, iodide is thermodynamically unstable in oxic seawater. The conversion (or reduction) of iodate to iodide may be mediated via biological activities. Since biological activities vary with the season, the conversion of iodate to iodide may also vary seasonally. The conversion (or oxidation) of iodide to iodate is thermodynamically feasible, but the mechanism is poorly known. Hydrogen peroxide, which is ubiquitous in surface seawater, may oxidize iodide to iodate.

Water samples were collected in the middle and lower Chesapeake Bay in different seasons between 1990 …


Hydrogeochemical Characterization Of The Alvord Valley Known Geothermal Resources Area, Harney County, Oregon, Anna Maria St. John Jun 1993

Hydrogeochemical Characterization Of The Alvord Valley Known Geothermal Resources Area, Harney County, Oregon, Anna Maria St. John

Dissertations and Theses

The Alvord Valley Known Geothermal Resources Area (KGRA) , located east of the Steens Mountain-Pueblo Mountains fault block in southeastern Oregon, is within the northern Basin and Range province. This investigation focuses on three thermal areas in the Alvord Basin: Borax Lake and the hot springs north of Borax Lake, Alvord Hot Springs and Mickey Springs.

Mickey Springs and the springs north of Borax Lake are boiling at the surface (94 and 95° C, respectively). Inflow temperatures to Borax Lake, measured at a depth of 30 m, are greater than 100° C. Surface temperatures for Alvord Hot Springs and a …


Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst Jun 1993

Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst

Masters Theses

Experiments were conducted in laboratory sand tanks to evaluate filter pack design criteria in an effort to improve free-product hydrocarbon recovery from sand aquifers. Filter sands were prepared and installed in the test tanks to examine the relative efficiency of two different grain sizes and two different grain-size distributions to imbibe kerosene from the formation sand and release it to their respective wells. Treatments of different chemical products were applied to other filter sands to create a hydrophobic coating on the grains. The hydrophobic coatings were tested on filter sands of different grain sizes and grain-size distributions and compared to …


A Fracture Analysis Of Glacial Tills In Southwest Michigan, Ralph L. Freed Jun 1993

A Fracture Analysis Of Glacial Tills In Southwest Michigan, Ralph L. Freed

Masters Theses

Fractures were recorded and measured at seven southwest Michigan glacial till locations to identify geometry and spacing. Strong preferred orientations were shown at azimuths of 110° and 140° for two sites, and at azimuths of 85°, 110°, and 135°, and at 44° and 167° for two sites. Several sites had numerous oblique fractures.

Thirty-eight azimuthal Wenner arrays and four Schlumberger surveys show apparent resistivities vary widely with depth of penetration and material composition. Eleven percent of azimuthal surveys show an elliptical data array coinciding with preferred orientation of an adjacent fracture set. The relationship between azimuthal survey and fractures is …


The Effects Of Composting Of Yard Wastes On The Ground-Water Quality: Wmu Farms Site, Kalamazoo, Michigan, Bryan Kirk Allen Jun 1993

The Effects Of Composting Of Yard Wastes On The Ground-Water Quality: Wmu Farms Site, Kalamazoo, Michigan, Bryan Kirk Allen

Masters Theses

In the rush to find alternatives to landfilling of yard waste, federal and state agencies have identified composting as the main solution. There is therefore a need to address the possible environmental problems which could be associated with such composting operations. Compost may contain nutrients, organic acids, pesticides, and metals which could leach through soils to the ground water posing a potential contamination problem.

At the WMU Farms Site, two sites have been used for the composting of leaves by the City of Kalamazoo. The physical and chemical hydrogeology of these sites were characterized.

The results suggest that the presence …


The Hydrogeology Of Bonnie Castle And Dustin Lakes And Its Relationship To Groundwater Contamination From The Kl Avenue Landfill, Kalamazoo County, Michigan, Joseph S. Hobin Jun 1993

The Hydrogeology Of Bonnie Castle And Dustin Lakes And Its Relationship To Groundwater Contamination From The Kl Avenue Landfill, Kalamazoo County, Michigan, Joseph S. Hobin

Masters Theses

The objectives of this investigation were to explain the hydrogeology of Bonnie Castle and Dustin Lakes and to assess the water quality of the lake environments with respect to possible impact from the KL Avenue Landfill.

The surface water/groundwater relationship was determined by the installation of mini-piezometer nests and seepage meters at selected study stations along the shoreline of each lake. Field data were augmented with groundwater and surface water chemical analyses, lake depth profiles and geologic cross-sections.

The result of this research was the characterization of Bonnie Castle Lake as a perched recharge lake and Dustin Lake as a …


Groundwater Chemistry Analysis Of The Saginaw Formation In Delhi Township, Michigan, Sam L. Kitchin Jun 1993

Groundwater Chemistry Analysis Of The Saginaw Formation In Delhi Township, Michigan, Sam L. Kitchin

Masters Theses

Groundwater chemistry and well data provided by the Ingham County (Michigan) Health Department were used to evaluate the distribution of inorganic chemical constituents in the groundwater flow system of the Saginaw Formation, in Delhi Township, Michigan. The data also were used to study the distribution of chemical constituents with respect to different rock types of the Saginaw Formation. The data were analyzed to examine if variations in the concentrations of the chemical constituents and the values of other chemical parameters relate to rock-water interactions, groundwater flow systems, or groundwater contamination.

The results indicate that patterns of increasing or decreasing concentrations …


Gravity Modeling Of A Patch Reef In Allegan County, Michigan, Mei Leng Wong Jun 1993

Gravity Modeling Of A Patch Reef In Allegan County, Michigan, Mei Leng Wong

Honors Theses

The study of the Diamond Springs oil field in Allegan County focuses on the use of gravity to delineate individual reef buildups. The Diamond Springs oil field is a small patch reef located in northern Allegan County, Michigan. The reef, which is approximately 1400 feet deep, is located within the Middle Devonian Traverse Limestone and was deposited in an open shelf, carbonate platform and lagoonal environment. The reef covers an area of approximately one square mile and has a vertical relief of 30 to 80 feet. These porous reef materials are commonly buried by muds or evaporites resulting in ideal …


Lithostratigraphy, Structure, And Metamorphism Of A Crystalline Thrust Terrane, Western Inner Piedmont, North Carolina, Timothy L. Davis May 1993

Lithostratigraphy, Structure, And Metamorphism Of A Crystalline Thrust Terrane, Western Inner Piedmont, North Carolina, Timothy L. Davis

Doctoral Dissertations

The geology of the western Inner Piedmont of North Carolina, from knowledge gained in an area called the Columbus Promontory, is characterized by a stack of crystalline thrust sheets. In this study the stratigraphic, structural, and metamorphic development of this crystalline thrust terrane was examined.

The lithostratigraphic framework of the Columbus Promontory is divisible into four distinct and mappable rock units that include the Henderson Gneiss, Sugarloaf gneiss, Poor Mountain Formation, and the Mill Spring Complex. This lithostratigraphic framework helps define three crystalline thrust sheets within the Columbus Promontory herein, called the Tumblebug Creek, Sugarloaf Mountain, and Mill Spring thrust …


Structural Development, Strain History, And Timing Of Deformation In The Eastern Great Smoky Mountains, Jeffrey B. Connelly May 1993

Structural Development, Strain History, And Timing Of Deformation In The Eastern Great Smoky Mountains, Jeffrey B. Connelly

Doctoral Dissertations

The present investigation reveals that the Greenbrier and Dunn Creek thrust sheets preserve well-formed ramp-related folds within the Great Smoky Mountains area. The Greenbrier thrust sheet preserves a ramp anticline at klippes of the Greenbrier thrust sheet in the eastern Great Smoky Mountains that can be traced discontinuously to the western Great Smoky Mountains where this anticline has been modified by later displacement along the Rabbit Creek fault. A ramp-related fold is also preserved in the main Greenbrier thrust sheet. The main Greenbrier fault was subsequently folded by an underlying ramp anticline within the Dunn Creek thrust sheet. These earliest …


Hydrogeology And Hydrochemistry Of The Delta Wadi El-Arish Area Sinai Peninsula, Egypt, Medhat A. El-Bihery May 1993

Hydrogeology And Hydrochemistry Of The Delta Wadi El-Arish Area Sinai Peninsula, Egypt, Medhat A. El-Bihery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Delta Wadi El-Arish, Sinai Peninsula, Egypt, forms one of the most important parts of Egypt for industrial and agricultural expansion projects. This study focuses on the hydrogeology and the hydrochemistry of the Quaternary aquifer in the delta Wadi El-Arish area. Accurate information about the groundwater characteristics of the Quaternary aquifer will allow implementation of a sound water management policy for the Wadi El-Arish area.

The objectives of this study include: 1) determining the relationships between groundwater extraction and water levels and water quality using water-level measurements, total extraction of the wells, and chemical analyses of water samples; 2) determining the …


Internal Deformation, Evolution, And Fluid Flow In Basement-Involved Thrust Faults, Northwestern Wyoming, James V. Goddard May 1993

Internal Deformation, Evolution, And Fluid Flow In Basement-Involved Thrust Faults, Northwestern Wyoming, James V. Goddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An integrated field, microstructure, fracture statistic , geochemistry, and laboratory permeability study of the East Fork and White Rock fault zones, of similar age and tectonic regime but different structural level and hydrogeologic history, provides detailed information about the internal deformation and fluid flow processes in fault zones. The primary conclusions of this research are: 1) Fault zones can be separated into subzones of protolith, damaged zone , and gouge /cataclasite, based on physical morphology and permeability structure. At deep structural levels, gouge/cataclasite zones are more evolved (thicker with increased grain size reduction) due to strain localization, higher pressure and …


Geochemistry, Alluvial Facies Distribution, Hydrogeology, And Groundwater Quality Of The Dallas-Monmouth Area, Oregon, Rodney R. Caldwell Apr 1993

Geochemistry, Alluvial Facies Distribution, Hydrogeology, And Groundwater Quality Of The Dallas-Monmouth Area, Oregon, Rodney R. Caldwell

Dissertations and Theses

The Dallas-Monmouth area, located in the west-central Willamette Valley, Oregon, consists of Tertiary marine and volcanic bedrock units which are locally overlain by alluvium. The occurrence of groundwater with high salinities has forced many rural residents to use public water supplies. Lithologic descriptions from driller's logs, geochemical (INAA), and x-ray diffraction analyses were used to determine alluvial facies distribution, geochemical and clay mineral distinctions among the units, and possible sediment sources. Driller's log, chemical and isotopic analysis, and specific conductance information from wells and springs were used to study the hydrogeologic characteristics of the aquifers and determine the distribution, characteristics, …


Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz Apr 1993

Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz

Masters Theses

Data on the distributions of VOC’s (volatile organic compounds), principally trichloroethane and dichloroethylenes, in a shallow sand and gravel aquifer near Rockford, IL have been collected for a number of years. Synoptic sampling events from a dense monitoring well network within a greater than 4 mi^2 area, provide the basis for the evaluation of sources of variability in concentrations in space and time. Sampling, and analysis-related variability in these data contribute less than 10% of total variance. Spatial and temporal variability over periods of months to years are significant Results suggest that contaminant distributions can be resolved best by using …


Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett Apr 1993

Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett

Masters Theses

Laboratory sand tank experiments and two field studies were conducted to determine filter-pack designs that would increase the hydrocarbon flow rate into hydrocarbon recovery wells. Previous laboratory experiments have shown that using filter-packs of Teflon chips or sands treated with a water repellent spray will increase the rate of hydrocarbon recovery into wells in laboratory bail down test experiments.

The results of the laboratory investigations suggest that using a hydrophobic filter-pack with a median grain-size of 2.5-3.5 greater than that of the aquifer will provide the greatest rate of hydrocarbon recovery.

In two field studies, wells constructed with a hydrophobic …


The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery Apr 1993

The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery

OES Theses and Dissertations

Hydrogen sulfide is a poorly quantified component of the global sulfur cycle. In seawater, its dissolved species (dissolved sulfide) can react with trace metals to form dissolved complexes and insoluble compounds. Therefore, the study of dissolved° sulfide in the open ocean can yield a better understanding of the biogeochemical cycles of sulfur and trace metals.

The biogeochemical cycling of dissolved sulfide was examined using specially developed sampling and analytical methods. In the western North Atlantic and central Equatorial Pacific Oceans, total dissolved sulfide concentrations ranged from /L; they were highest, in the mixed layer and decreased with depth. The depth …


Paleocene To Miocene Foraminifera From A Well Near Gloucester, Virginia, Nelson Stanley Ford Apr 1993

Paleocene To Miocene Foraminifera From A Well Near Gloucester, Virginia, Nelson Stanley Ford

OES Theses and Dissertations

Lithologic analysis of twenty-one core samples from a well near Gloucester, Virginia, when compared to published descriptions of formations occurring in the study area, indicates the presence of five formations. From oldest to youngest these units are the Aquia (late Paleocene), Nanjemoy (early Eocene), Chickahominy (late Eocene), Old Church (late Oligocene and early Miocene), and Eastover (late Miocene) formations. Comparison of the stratigraphic ranges of key planktic and benthic foraminifera from each of the core samples shows chronological agreement with previously published ages for each of these formations.

Paleoenvironmental analysis of each of the formations in the well is based …


Recent Benthic Foraminifera, Petrology, And Implications For Recent Transport In Wilmington And South Heyes Submarine Canyons, U.S. Atlantic Continental Margin, Jason James Lundquist Apr 1993

Recent Benthic Foraminifera, Petrology, And Implications For Recent Transport In Wilmington And South Heyes Submarine Canyons, U.S. Atlantic Continental Margin, Jason James Lundquist

OES Theses and Dissertations

Two hundred and forty-six species of benthic foraminifera have been recognized in fourteen short cores (≤ 24cm) taken from within the Wilmington and South Heyes submarine canyons along the slope and rise of the United States Atlantic Continental Margin. Of these one hundred and forty-five species were identified to the species level, thirty were closely related to known species, sixty-six could not be assigned specific names, and five species were of uncertain generic placement. The petrologic character of the sediments was determined for each of the seventy-eight micropaleontogical samples.

Cluster analysis of benthic foraminiferal data identified twelve groups which, together …


Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood Apr 1993

Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood

OES Theses and Dissertations

This study tested the validity of using intraspecific variation in benthic foraminifera as a means for determining Pleistocene paleobathymetry. Canonical variate analysis was used as a means for determining visually undetectable but statistically significant differences in the morphology of selected species. Two species, Cassidulina subglobosa and Uvigerina peregrina, were collected from Pleistocene well cuttings from the northwest Gulf of Mexico. The canonical analysis involved comparing the intraspecific variation of these Pleistocene species to their counterparts occurring in the modern Gulf of Mexico, where intraspecific variation was previously analyzed and found to be sufficient to allow detection of bathymetric differences …


Petrology Of A Large Granophyre-Rich Mesozoic Diabase Dike Near Farmville, Virginia, Philip Thomas Rogan Apr 1993

Petrology Of A Large Granophyre-Rich Mesozoic Diabase Dike Near Farmville, Virginia, Philip Thomas Rogan

OES Theses and Dissertations

Up to 37% granophyre occurs in the center of a 150m-wide Mesozoic diabase dike near Farmville, Virginia. The exceptional abundance of granophyre compared with other Mesozoic diabase dikes suggests unusual petrogenetic processes are involved in formation of the dike. Petrographic analyses show that granophyre increases from 5-10% near the flanks of the dike to a maximum of 37% in the core of the dike, and that granophyre distribution is approximately symmetrical about the center of the dike. Major and trace element concentrations parallel variations in the modal abundance of granophyre, with SiO2 , Na2O and K2 …


Lithofacies Of The Pliocene-Pleistocene Lucayan Limestone, Great Abaco Island, Little Bahama Bank, Mary K. Mullen Apr 1993

Lithofacies Of The Pliocene-Pleistocene Lucayan Limestone, Great Abaco Island, Little Bahama Bank, Mary K. Mullen

OES Theses and Dissertations

Petrographic and sedimentologic analyses of eleven shallow subsurface cores (3 to 19 meters in length) from the Lucayan Limestone where it occurs along northeastern Great Abaco Island (little Bahama Bank) are used to delineate five carbonate lithofacies. The most prevalent lithofacies is a mottled, nonskeletal, peloidal packstone to grainstone. Other lithofacies include a rudstone, a laminated nonskeletal grainstone, a crossbedded grainstone and a mudstone-wackestone.

Cementation varies from poor to very well cemented core intervals. Cements observed included equant granular, equant blocky, drusy, meniscus, and needle fiber "whisker" cements. These cements reflect a variety of diagenetic environments such as the vadose, …