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Articles 271 - 300 of 339
Full-Text Articles in Earth Sciences
Increased Effluent Dosage Effects On Septic System Absorption-Field Products Of Differing Architecture Types, Andrew Richard Gibbons
Increased Effluent Dosage Effects On Septic System Absorption-Field Products Of Differing Architecture Types, Andrew Richard Gibbons
Graduate Theses and Dissertations
Nationwide, approximately 20% of all homes use an on-site septic system as a form of household wastewater treatment. Since karst features are prevalent throughout the Ozark Highlands region of Northwest Arkansas, surface and groundwater resources are susceptible to contamination. Therefore, the objectives of this study were to evaluate the effects of soil condition (i.e., wet and dry) and absorption-field-product architecture type [i.e., chamber, gravel-less-pipe (GLP), polystyrene-aggregate (PSA), and pipe-and-aggregate (PA)] on in-product solution storage and biomat thickness in a profile-limited soil, and to identify the long-term acceptance rate (LTAR) of each product. During Phase I of this study (i.e., March …
Carbon Dioxide Emissions From Switchgrass And Cottonwood Grown As Bioenergy Crops In The Lower Mississippi Alluvial Valley, Michele Lea Helton
Carbon Dioxide Emissions From Switchgrass And Cottonwood Grown As Bioenergy Crops In The Lower Mississippi Alluvial Valley, Michele Lea Helton
Graduate Theses and Dissertations
Marginal land of the Lower Mississippi Alluvial Valley (LMAV) has the potential to be utilized for the production of bioenergy feedstocks. Soil respiration is the gaseous emission of carbon dioxide (CO2) from microbes and plant roots in the soil, and these emissions play an important role in the global cycling of carbon. Soil respiration can act as a positive feedback affecting climate change, and has been shown to vary depending on soil moisture, temperature, and vegetation. The objectives of this study where to evaluate the effects of land use [switchgrass (Panicum virgatum), cottonwood (Populus deltoides …
Investigation Of The Flow And Fate Of Nitrate In Epikarst At The Savoy Experimental Watershed, Northwest Arkansas, Jozef Laincz
Investigation Of The Flow And Fate Of Nitrate In Epikarst At The Savoy Experimental Watershed, Northwest Arkansas, Jozef Laincz
Graduate Theses and Dissertations
Many karst aquifers are at high risk of nitrate contamination due to a combination of vulnerable geology characterized by thin soils and conduit flow, and excess inputs of nutrients from animal feeding operations. One zone that is present in many karst regions and could play an important role in nitrate attenuation due to properties such as increased residence time and matrix-water contact is the upper, weathered portion of karst, the epikarst. However, the understanding of this role is lacking, and the objective of this dissertation was to elucidate it. The fate of nitrate in the epikarst was traced along a …
Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe
Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe
Graduate Theses and Dissertations
A compacted clay liner (test pad) was constructed and instrumented with volumetric water content and soil matric potential sensors to determine soil water characteristic curves (SWCC) and hydraulic conductivity (k) functions. Specifically, the compacted clay liner was subjected to an infiltration cycle during a sealed double ring infiltrometer (SDRI) test followed by a drying cycle. After the drying cycle, Shelby tube samples were collected from the compacted clay liner and flexible wall permeability (FWP) tests were conducted on sub-samples to determine the saturated hydraulic conductivity. Moreover, two computer programs (RETC and UNSAT-H) were utilized to model the SWCCs and k-functions …
Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz
Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz
Graduate Theses and Dissertations
The Neolithic Revolution marked a dramatic change in human subsistence practices. In order to explain this change, we must understand the motive forces behind it. Researchers have proposed many different stimuli, with most theories invoking environmental dynamics, human population density increases beyond environmental carrying capacity, and the natural outgrowth of human and plant/animal interactions. However, unanswered questions remain concerning the mechanics of animal domestication. Traditional studies of changing faunal morphology and skeletal population profiles offer some clues, but such research has had limited success identifying stages intermediate between wild and domesticated forms, which makes it difficult to discern initial attempts …
The Significance Of Dolomitized Hunton Strata In The Kinta And Bonanza Fields Of The Arkoma Basin, Christopher William Trotter
The Significance Of Dolomitized Hunton Strata In The Kinta And Bonanza Fields Of The Arkoma Basin, Christopher William Trotter
Graduate Theses and Dissertations
The Hunton Group has been a prolific hydrocarbon-producing reservoir across much of Oklahoma and western Arkansas. The group is a Silurian-Devonian aged interval that is comprised of sequences of limestone, dolomite, and calcareous shale. The group is divided into several formations. The subdivisions include the Chimneyhill Subgroup, Henryhouse, Haragan and Bois d'Arc Formations. Reservoir quality in the Hunton Group is significantly dependent upon the diagenetic events and depositional environments of the sediments. Most hydrocarbon production, from within the Hunton Group, comes from members that have undergone dolomite replacement of the parent limestone.
The higher amounts of porosity and permeability are …
Comparisons Of Hydrogeologic Modeling Methods To Define Capture Zones For Public Water Supply Wells In Northern Arkansas, Paula Anderson
Comparisons Of Hydrogeologic Modeling Methods To Define Capture Zones For Public Water Supply Wells In Northern Arkansas, Paula Anderson
Graduate Theses and Dissertations
The usefulness, applicability, and practicality of more complex and resource consuming methods for groundwater modeling has been in question since computer based groundwater modeling was established (Anderson, 1992). In many situations, computer modeling of groundwater flow is a necessity and useful for extrapolating data where none exists or it is impossible or impractical to acquire. However, when delineating a recharge area around a public water well for protection purposes, it is unknown if more detailed computer modeling results are better than simpler hydrologic calculations and site study. In the case of public drinking water supply wells located in various aquifers …
Effects Of Instrumentation On Dental Microwear Textures: Reanalysis And Augmentation Of An Early Hominin Sample, Anna Jacquelyn Ragni
Effects Of Instrumentation On Dental Microwear Textures: Reanalysis And Augmentation Of An Early Hominin Sample, Anna Jacquelyn Ragni
Graduate Theses and Dissertations
Dental microwear texture analysis has been refined to a methodology relying upon scanning confocal microscopy for its advantages of repeatability and standardized quantification. A new instrument, the Plu Neox (Sensofar Corp.) confocal profiler recently entered the market, sparking questions among dental anthropologists related to the advantages and efficacy of this new technology, which has better resolution and lighting properties than previously available white-lighted based confocal profilers. This thesis reports on three complementary studies that set out to evaluate the comparability of the Plu Neox to the Plu Standard system and assess its ability to distinguish primates on the basis of …
Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker
Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker
Graduate Theses and Dissertations
Nitrogen (N2) fixation can give certain species of cyanobacteria a competitive advantage in lake and reservoir phytoplankton. These species of cyanobacteria, along with others that cannot fix N2, can form toxic compounds that impair water quality when present in high concentrations. N2 fixation rates may be substantial in small (< 1.0 km2), temperate reservoirs since these systems experience thermal stratification and often nitrogen (N) limitation throughout a substantial proportion of the year. However, the effects of N2 fixation on N cycling, alleviation of short-term N limitation, and water quality are not well-understood. A mesocosm experiment and ecosystem-scale observational study were conducted to 1) determine the efficiency of N2 fixation under varying N relative to phosphorus (P) supply, 2) examine the effects of N2 fixation on autotrophic biomass accumulation and microcystin production, and 3) measure N2 fixation rates and importance to autotrophic N demand and zooplankton N assimilation. Results of the mesocosm experiment indicated that N2 fixation was increased at low N:P supply under high P. However, N2 fixation was inefficient at alleviating N limitation when fixed N was the primary source of N. Additionally, microcystin production occurred only at high N:P supply when N2 fixation was low, indicating that reducing external N inputs may have a positive effect on water quality. Results of whole-reservoir determination of N2 fixation using seston δ15N natural abundances indicated that N2 fixation rates throughout the warm season were substantial and influenced by water temperature. Annual N2 fixation rates ranged from 2.2 - 6.6 g N m-2 yr-1, and contributed up to 19% of the annual autotrophic N demand. Zooplankton were assimilating fixed N in most of the study reservoirs, representing a possible mechanism of ecosystem fixed N retention. Collectively, these results suggest that N2 fixation plays a substantial role in N cycling in small, temperate reservoirs, but likely cannot alleviate short-term N limitation.
Subsurface Sequence Stratigraphy And Reservoir Characterization Of The Mississippian Limestone (Kinderhookian To Meramecian), South Central Kansas And North Central Oklahoma, Thomas Cahill
Graduate Theses and Dissertations
Both conventional and unconventional Mississippian reservoirs in the mid-continent are largely comprised of chert-rich carbonates of Osagean and Meramecan age. The conventional reservoir target is the Mississippian "chat," a high porosity, chert residuum interval found immediately beneath the Mississippian-Pennsylvanian unconformity. The unconventional reservoir target occurs in the lower porosity, cherty, mud-rich intervals that occur in the lower portion of the Mississippian succession.
There has been considerable debate surrounding the sequence stratigraphic interpretations, depositional models, and formation names applied to the reservoir intervals within the subsurface. Another major issue with regard to the subsurface is the stratigraphic position and origin of …
Depositional History And Stratigraphic Framework Of Upper Cretaceous (Campanian To Maastrichtian) Strata In The Minerva-Rockdale Oil Field Of Milam County And Adjacent Counties, Texas., Adam Thomas Martin
Graduate Theses and Dissertations
First discovered in 1921, the Minerva-Rockdale Oil Field (MROF) has experienced a recent resurgence of drilling. The targeted Navarro Group is Upper Cretaceous (Maastrichtian) in age and ranges in depth from approximately 100 to 3000+ ft. (subsea). Several thin elongated sandy zones within the Kemp clay of the Corsicana (Navarro) Formation, are the current targets for oil production. These sandy zones are informally divided into the Navarro `A' and `B' and their depositional morphology is described by the shelf plume model, as proposed by Patterson (1983).
Despite the mature nature of the MROF and surrounding area, only a small number …
Analysis Of Environmental Influences On Dressed Stone Decay: A Case Study Of Tafoni Development On A Hewn Djinn Block In Petra, Jordan, Kaelin M. Groom
Analysis Of Environmental Influences On Dressed Stone Decay: A Case Study Of Tafoni Development On A Hewn Djinn Block In Petra, Jordan, Kaelin M. Groom
Graduate Theses and Dissertations
Petra, Jordan captivates tourists and researchers with its dramatic sandstone cliffs, Nabatean, Roman, Byzantine and Roman architecture, and rich cultural heritage. However, increasing tourism in the valley is exacerbating stone degradation and complicating heritage management. This research analyzed environmental influences on dressed stone decay via tafoni development and evaluating cell evolution on an isolated hewn feature, known as Djinn Block X. Resembling other sandstone blocks found in the area, this irregular sandstone monument exhibits faces ranging in size from 2.5m by 3.5m to 3.9m to 4.2m (29m perimeter). Protruding features, incisions along the top, and a large platform attached to …
Fertilizer Nitrogen Uptake Efficiency In Soft Red Winter Wheat And The Ability Of N-Star To Detect Alkaline Hydrolyzable Nitrogen In Crop Residues, Lana Aubrey Clark
Fertilizer Nitrogen Uptake Efficiency In Soft Red Winter Wheat And The Ability Of N-Star To Detect Alkaline Hydrolyzable Nitrogen In Crop Residues, Lana Aubrey Clark
Graduate Theses and Dissertations
Soil testing methods such as the Illinois Soil Nitrogen Test (ISNT) and Direct Steam Distillation (DSD) have been developed which measure alkaline hydrolyzable-N (AH-N) as a means of estimating potentially mineralizable-N. Crop residues play an important role in N cycling. However, the ability of the ISNT and DSD methods to determine AH-N within crop residues is unknown. Therefore, the first objective of this study was to determine the ability of the ISNT and DSD to quantify potentially mineralizable-N within five different crop residues common to Arkansas. Corn (Zea mays L.), soybean (Glycine max, L.), wheat, rice (Oryza sativa, L.), and …
Structure And Stratigraphy Of A Complex Anticlinal Feature, Backbone Anticline, Arkoma Basin, Arkansas, Shailyn Marie Abbott
Structure And Stratigraphy Of A Complex Anticlinal Feature, Backbone Anticline, Arkoma Basin, Arkansas, Shailyn Marie Abbott
Graduate Theses and Dissertations
The Arkoma Basin of Arkansas and Oklahoma formed in the Ouachita foreland during the late Mississippian and Pennsylvanian periods (about 290-to 330 million years ago). The basin developed in response to convergent tectonic boundaries that closed obliquely from west to east associated with Ouachita orogenic event. The Backbone anticline in the northern Arkoma Basin is a prominent product of this convergence, and represents the first major component of this study. The structure is asymmetric with beds on the southern limb dipping steeply to the south. It is also expressed topographically as a prominent ridge that trends eastward from the Oklahoma-Arkansas …
Mechanical Stratigraphy Of The Mississippian In Osage County, Oklahoma, Caleb James Jennings
Mechanical Stratigraphy Of The Mississippian In Osage County, Oklahoma, Caleb James Jennings
Graduate Theses and Dissertations
The Mississippian formation of Oklahoma and Kansas has recently developed as a world class unconventional reservoir with wells producing up to 800 bbl/day. The Mississippian is composed of multiple distinct lithologic zones including limestone, hard chert, and soft tripolitic chert. These zones are difficult to discern with traditional log correlation, but mechanical stratigraphy has the potential to improve previous correlations of the Mississippian.
This study uses full wave sonic logs from Osage County, OK to analyze the elastic properties of the Mississippian. Our work computes isotropic elastic parameters in an effort to partition the Mississippian section into units that may …
Methane Emissions And Ammonia Volatilization From Drill-Seeded, Delayed-Flood Rice On A Silt-Loam Soil In Arkansas, Christopher Wade Rogers
Methane Emissions And Ammonia Volatilization From Drill-Seeded, Delayed-Flood Rice On A Silt-Loam Soil In Arkansas, Christopher Wade Rogers
Graduate Theses and Dissertations
The Environmental Protection Agency (EPA) currently uses a single methane (CH4) emissions factor of 160 kg CH4-C ha-1 for a primary rice (Oryza sativa L.) crop. The emissions factor is based on studies that do not adequately represent current management practices in Arkansas. Another concern is pre-flood fertilizer nitrogen (N) management, as the common N source, urea, is prone to loss via ammonia (NH3) volatilization. Thus, the objective of this research was to investigate trace gas emissions from rice on a silt-loam soil, including CH4 emissions as influenced by nitrogen (N) fertilization (i.e., optimal N and no N) in 2011, …
Structural And Stratigraphic Transition From The Arkoma Shelf Into The Arkoma Basin During Basin Subsidence; Arkoma Basin, Northwest Arkansas, Elizabeth Whitney Studebaker
Structural And Stratigraphic Transition From The Arkoma Shelf Into The Arkoma Basin During Basin Subsidence; Arkoma Basin, Northwest Arkansas, Elizabeth Whitney Studebaker
Graduate Theses and Dissertations
The Arkoma basin is an arcuate Paleozoic structural feature in the Ouachita foreland that extends from central Arkansas and westward into southeastern Oklahoma. The Arkoma shelf lies immediately north of the basin and is comprised of Cambrian to Pennsylvanian age sedimentary rocks. In northwestern Arkansas, the stratigraphic and structural transition from the shelf into the northern portion of the Arkoma basin is poorly defined.
Wireline logs were used to construct a series of three north to south cross sections, as well as two along-strike west to east cross sections to examine Morrowan and lower Atokan age strata. In addition to …
Porosity Development Within Lobes To Downslope Ramp Deposits On A Prograding Carbonate Shelf Of The Kinderhookian To Osagean Series In Northwest Arkansas, Elizabeth Marchese
Porosity Development Within Lobes To Downslope Ramp Deposits On A Prograding Carbonate Shelf Of The Kinderhookian To Osagean Series In Northwest Arkansas, Elizabeth Marchese
Graduate Theses and Dissertations
Carbonate bodies with lobate geometries form a substantial part of the Osagean (early Mississippian) section in northwest Arkansas. The purpose of this study is to isolate and describe a single lobe from three-dimensional exposures in quarry walls to provide criteria by which lobe and lobe porosity can be recognized in the subsurface. Carbonate sediment generated on the Mississippian Burlington shelf moved southward by gravity flows from the shelf margin to positions on a prograding ramp in Arkansas where overlapping deposits with lobate geometries accumulated. These deposits are recognized in outcrops of the Boone Formation. Stratigraphic units within the Boone are …
Application Of Detrital Zircon Geochronology To Determine The Sedimentary Provenance Of The Middle Bloyd Sandstone, Arkoma Shelf, Northern Arkansas, Greg Michael Buratowski
Application Of Detrital Zircon Geochronology To Determine The Sedimentary Provenance Of The Middle Bloyd Sandstone, Arkoma Shelf, Northern Arkansas, Greg Michael Buratowski
Graduate Theses and Dissertations
The sedimentary provenance of the middle Bloyd sandstone and subsequent sediment transport and dispersal patterns of the Early Pennsylvanian were interpreted by utilizing U-Pb detrital zircon geochronology. Eight middle Bloyd sandstone samples were analyzed. A total of 855 concordant analyses resulted. Peaks occurred at 350-500 Ma, 950-1200 Ma, 1300-1500 Ma, 1800-2300 Ma, and >2500 Ma. These peaks were determined to represent crystalline source rocks on the Laurentian craton from Acadian-Taconic, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Archean Superior Provinces respectively. Grenville age zircons were the most common zircons identified in the middle Bloyd sandstone samples. The Appalachian Mountain region is …
3d Seismic Mapping Of Probable Tripolitic Chert Bodies In Osage County, Oklahoma, Richard Craddock Benson
3d Seismic Mapping Of Probable Tripolitic Chert Bodies In Osage County, Oklahoma, Richard Craddock Benson
Graduate Theses and Dissertations
The Mississippi Lime play is an important recent oil and gas development in the mid-continent of the United States. In April of 2007, Chesapeake Energy Corporation used horizontal drilling and tracing to bring the Howell 1-33H well online. This well revitalized the Mississippi Lime play, expanding exploration with potential Mississippian reservoirs.
The Mississippian section is a complex carbonate reservoir containing several distinct lithologies. An important Mississippian lithology known from outcrops in Arkansas and Missouri is tripolitic chert, or tripolite; a bleach, highly diagenetically altered, silica rock with high porosity, low density, and high permeability. Tripolite is an important reservoir target …
Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith
Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith
Graduate Theses and Dissertations
Sustainability in agriculture is paramount to assuring continued production from our most naturally fertile soils. Storing carbon (C) in soil as organic matter through sustainable agricultural management practices can both remove atmospheric C and improve soil quality. The objective of this study was to evaluate the long-term effects of water management (irrigation and dryland), residue management [burn and no-burn, conventional (CT) and no-tillage (NT)] and residue/fertility level (high and low) on soil respiration and aggregate stability in a wheat- (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], double-crop system in a silt-loam soil (Aquic Fraglossudalf) in the Mississippi River Delta …
Quantitative Trait Loci Associated With Waterlogging Tolerance In A Soft Red Winter Wheat Mapping Population, Diana Carolina Ballesteros Benavides
Quantitative Trait Loci Associated With Waterlogging Tolerance In A Soft Red Winter Wheat Mapping Population, Diana Carolina Ballesteros Benavides
Graduate Theses and Dissertations
Waterlogging is caused when water stays superficially in the soil for an extended period of time, creating an anaerobic environment which decreases plant growth and grain yield at maturity. Despite the impact of waterlogging on wheat production both globally and in the southeastern U.S., very little is known about the genetic control of waterlogging tolerance in wheat. The objective of this study was to determine the amount of genetic variation for vegetative stage waterlogging tolerance present within a wheat recombinant inbred line (RIL) population and to identify quantitative trait loci (QTL) associated with tolerance and productivity. Experiments were carried out …
Bedrock Geological Map Of The Rockhouse Quadrangle, Carroll And Madison Counties, Arkansas, Douglas Eben Jones
Bedrock Geological Map Of The Rockhouse Quadrangle, Carroll And Madison Counties, Arkansas, Douglas Eben Jones
Graduate Theses and Dissertations
A digital geologic map of the Rockhouse quadrangle, Carroll and Madison counties, Arkansas, was created on a 1:24,000 scale using ArcMap 10 and Photoshop CS4. The data obtained in the field are digitized onto the United States Geological Survey (USGS) digital raster graphic (DRG) of the Rockhouse quadrangle. The geology in the Rockhouse quadrangle consist entirely of sedimentary rocks that are Paleozoic ranging from Lower Ordovician to Mississippian in age. The Ordovician System is represented by the Cotter, Powell, Everton, and St. Peter Formations. The Cotter and Powell are the prominent bluff forming units throughout the quadrangle and along the …
Hydrogeology And Chemical Characterization Of Hydrocarbon In Domestic Water Wells, Rancho Villa Subdivision, Rogers, Arkansas, Janelle Renee Sherman
Hydrogeology And Chemical Characterization Of Hydrocarbon In Domestic Water Wells, Rancho Villa Subdivision, Rogers, Arkansas, Janelle Renee Sherman
Graduate Theses and Dissertations
This project is centered on the Rancho Villa community in Rogers, Arkansas where several residents have had hydrocarbon contamination in their domestic water wells. The goal of this project was to understand the hydrogeology in the study area, characterize the contaminant chemically, and determine the source of the contaminant. The hydrogeology of the area was determined from previous theses. Seventeen samples were taken from the wells in the Rancho Villa community; each sample was analyzed for geochemical parameters and by Gas Chromatography/Mass Spectrometry (GC/MS) for organic compounds analysis. Four of the 17 samples had a visible non-aqueous layer of hydrocarbon …
Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan
Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan
Graduate Theses and Dissertations
This study looks at two iron-rich phyllosilicates, which may be present on Mars. The minerals, greenalite and hisingerite, are rich in iron-II and iron-III, respectively. Small samples (~0.40 grams) of each mineral were crushed and heated in a Lindberg Tube Oven for approximately twenty-four hours at temperatures selected to mimic lava flows and impact events. Following heating, each sample was placed in a Fourier Transform Infrared (FT-IR) spectrometer to collect the near- and mid-infrared spectra. The spectra allowed for these terrestrial analogs to be analyzed with regards to how their structure breaks down with increasing temperature. The samples' colors were …
Sedimentary Provenance Of The Wedington Member, Fayetteville Shale, From Age Relations Of Detrital Zircons, William Tyson Cains
Sedimentary Provenance Of The Wedington Member, Fayetteville Shale, From Age Relations Of Detrital Zircons, William Tyson Cains
Graduate Theses and Dissertations
U-Pb geochronology of detrital zircons collected from the Chesterian Wedington Sandstone allows interpretation of sediment provenance and dispersal patterns in the southern midcontinent during the Late Mississippian. Detrital zircons analyzed from six samples of Wedington Sandstone yielded a final result of 565 concordant analyses used for interpretation. Results are plotted as Probability-Density Plots to interpret the spectrum of ages. Significant peaks occurred at 350-500 Ma, 950-1250 Ma, 1300-1500 Ma, 1600-1800 Ma, 1800-2300 Ma, and >2500 Ma. These peaks are interpreted as sourced by crystalline rocks within the Laurentian craton from Taconic-Acadian, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Superior Provinces. The …
A Geomechanical Study Of The Mississippian Boone Formation, Karen Nicole Mason Buckland
A Geomechanical Study Of The Mississippian Boone Formation, Karen Nicole Mason Buckland
Graduate Theses and Dissertations
The Boone Formation in northwest Arkansas is a chert-limestone sequence analogous to the subsurface Mississippi Lime reservoir in parts of Oklahoma and Kansas. It has low permeability and produces via horizontal drilling and hydraulic fracturing. The response to stimulation by fracturing is dependent on the quantity of chert in the area. Chert nodules and laterally extensive chert layers in the sequence are variable. Locally, cm- to dm-scale chert bedding is continuous and comprises up to 50% of the outcrop. Elsewhere, the chert is nodular and intermittent.
Samples collected from representative outcrops spanning the thickness and aerial extent of the formation …
Insights Into The Timing, Origin, And Deformation Of The Highland Mountains Gneiss Dome In Southwestern Montana, Usa, Lane Markes Boyer
Insights Into The Timing, Origin, And Deformation Of The Highland Mountains Gneiss Dome In Southwestern Montana, Usa, Lane Markes Boyer
Graduate Theses and Dissertations
The Highland Mountains of southwestern Montana offer a unique view of the Archean igneous and metamorphic rocks within the Great Falls tectonic zone (GFTZ). A Paleoproterozoic structural gneiss dome has been interpreted in the southern extent of the Highland Mountains. The ∼ 130km2 of exhumed metamorphic rocks and gneiss dome exposed in the Highland Mountains are the primary focus of this research. The formation of the Highland Mountains gneiss dome is proposed to be directly related to a northwest-side down detachment (the Steels Pass shear zone) that formed during terrane collision along the GFTZ. The field investigation determined foliation …
Analysis Of Tripolitic Chert In The Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas And Southwestern Missouri, Paul Marchand Minor
Analysis Of Tripolitic Chert In The Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas And Southwestern Missouri, Paul Marchand Minor
Graduate Theses and Dissertations
The Boone Formation in northwest Arkansas and southwestern Missouri exposes a nearly complete sequence of Lower Mississippian chert-bearing carbonates deposited by a single 3rd order transgression and regression. An abundant amount of chert that has replaced limestone highlights the Boone, but little is understood about the timing and development of chert in Lower Mississippian carbonates. Interpretation of the diagenetic history of the chert, in particular tripolite, has significant implications beyond the outcrop. Determining the origin, timing, and extent of tripolitic chert in the Lower Mississippian System improves reservoir characterization in subsurface petroleum reservoirs in the mid-continent that are laterally equivalent …
Assessment And Conceptualization Of Groundwater Flow In The Edwards Aquifer Through The Knippa Gap In Uvalde County, Texas, Jennifer Raye Adkins
Assessment And Conceptualization Of Groundwater Flow In The Edwards Aquifer Through The Knippa Gap In Uvalde County, Texas, Jennifer Raye Adkins
Graduate Theses and Dissertations
The Edwards aquifer is one of the major regional karst aquifers in the United States, with an average withdrawal of 950 million liters per day (L/d). This investigation focuses on the connection between the Uvalde pool and the San Antonio pool of the Edwards aquifer, known as the Knippa Gap, west of the San Antonio metropolitan area in Uvalde County. This is a major zone of recharge to the Edwards aquifer and is approximately 6.4 km wide. The Knippa Gap is bounded by northeast trending faults of the Balcones Fault Zone (BFZ) on the north (specifically the Cooks and Trio …