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Articles 271 - 300 of 355
Full-Text Articles in Geology
Loess And Its Geomorphic, Stratigraphic, And Paleoclimatic Significance In The Quaternary, Daniel R. Muhs
Loess And Its Geomorphic, Stratigraphic, And Paleoclimatic Significance In The Quaternary, Daniel R. Muhs
United States Geological Survey: Staff Publications
Loess is aeolian silt visible in the field as a sedimentary body. It covers a significant portion of the land surface of the Earth. Loess thickness, particle size, and carbonate content decrease downwind from sources, useful trends for paleowinds. Many loess sections consist of relatively thick deposits of mostly unaltered sediment with intercalated paleosols. Paleosols represent periods of landscape stability when loess deposition slowed significantly. Loess in most regions was deposited during glacial periods and paleosols formed during interglacial periods. Loess has the potential to record the timing and environment of glacial–interglacial cycles of the Quaternary on many continents.
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Lithogeochemical And Stable Isotope Characteristics Of Bristol And Northern Thorneloe Townships And Its Correlation With Gold Mineralization, Zachary Grant Stevison
Wayne State University Theses
The Porcupine Mining Camp located in the southwestend of the Abitibi Greenstone Belt has been mined extensively for its prolific precious and base metal enrichment. This study targeted Bristol and Northern Thorneloe, fifteen kilometers southwest of Timmins, ON, an area that is of economic interest for its gold mineralization. Rock samples were collected (drill- core and outcrop) throughout both townships and analyzed for their major and trace element composition, These were used to determine hydrothermal alteration signatures as well as specific elemental enrichment that relate to gold mineralization in Bristol-Thorneloe Township. Quartz-carbonate and quartz-carbonate-tourmaline vein samples were also collected near …
Class I Waste-Disposal Wells And Class Ii Brine-Injection Wells In Kentucky, Thomas N. Sparks, David C. Harris, J. Richard Bowersox
Class I Waste-Disposal Wells And Class Ii Brine-Injection Wells In Kentucky, Thomas N. Sparks, David C. Harris, J. Richard Bowersox
Map and Chart--KGS
This map shows locations of disposal wells permitted and regulated by the U.S. Environmental Protection Agency under parts of their Underground Injection Control program. Only UIC Class I and Class II disposal wells are illustrated and described. EPA defines Class I as industrial and municipal waste-disposal wells and Class II as oil- and gas-related injection wells (EPA, 2012a). Disposal wells are designed to protect underground sources of drinking water. The primary function of this map is to provide general information about type, name, location, geology, and depth of injection zone for these disposal wells on a statewide basis.
Joint Orientations In The Red River Gorge Geological Area, East-Central Kentucky, Steven L. Martin
Joint Orientations In The Red River Gorge Geological Area, East-Central Kentucky, Steven L. Martin
Information Circular--KGS
The Red River Gorge Geological Area and Clifty Wilderness Area of Daniel Boone National Forest and Natural Bridge State Park in east-central Kentucky provide an excellent opportunity to observe and study differential weathering and erosion, mass wasting, and jointing in the development of cliffs, rock shelters, and natural arches. Joints in the study area have varying orientations, but dominant northeast- and northwest-striking orientations are prevalent. Jointing in the study area is related to unloading of overburden and regional tectonic stresses. Unloading joints result from removal of overburden from a rock mass, and orientations of joints are controlled by either residual …
Determining The Sediment Source Area Through Petrographic Analysis Of The Hermosa Formation, Silverton, Southwestern Co, Kristina P. Pourtabib
Determining The Sediment Source Area Through Petrographic Analysis Of The Hermosa Formation, Silverton, Southwestern Co, Kristina P. Pourtabib
Undergraduate Honors Theses
The Pennsylvanian/Permian Hermosa Formation in southwestern Colorado is composed of arkosic sandstone, marine limestone, and shale that formed at a time when the region consisted of open-marine carbonate shelves and coastal plains. During the time of deposition, there were many tectonically active highlands in the region, including the Ancestral Rocky Mountains, San Luis Highlands, and the Uncompahgre, Emery, Zuni-Defiance-Kaibab Uplifts. Previous studies have attributed the source of the main sediment supply of the Hermosa Formation to the Uncompahgre branch of the Ancestral Rocky Mountains with smaller amounts of elastics from the Defiance-Zuni uplifts (Wengerd and Matheny, 1958; Wengerd and Strickland, …
Evolution Of High Tooth Replacement Rates In Sauropod Dinosaurs, Michael D. D'Emic, John A. Whitlock, Kathlyn M. Smith, Daniel C. Fisher, Jeffrey A. Wilson
Evolution Of High Tooth Replacement Rates In Sauropod Dinosaurs, Michael D. D'Emic, John A. Whitlock, Kathlyn M. Smith, Daniel C. Fisher, Jeffrey A. Wilson
Earth, Environment & Sustainability: Faculty Publications
Background: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates.
Methodology/Principal Findings: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined …
Three-Dimensional Hydrostratigraphy Of The Firth, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping In The Eastern Nebraska Water Resources Assessment (Enwra), Jesse T. Korus, R. Matthew Joeckel, Dana Divine
Three-Dimensional Hydrostratigraphy Of The Firth, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping In The Eastern Nebraska Water Resources Assessment (Enwra), Jesse T. Korus, R. Matthew Joeckel, Dana Divine
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki
Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki
Open Access Theses & Dissertations
This Dissertation consists of two different projects. The first project describes the results of an outcrop based sequence stratigraphic study of the Albian Cox Sandstone in the Indio Mountains of west Texas. The depositional environment of the Cox Sandstone ranges from shallow marine to the coastal plain deposited in four sequences where sequence 1 and sequence 2 consists of transgressive system tracts (TST) followed by highstand system tracts (HST). The highstand system tract (HST) is missing in sequence 3 and the transgressive systems tract is missing in sequence 4. The Cox changes in thickness from 320 m in the northern …
Application Of Various Remote Sensing And Aerial Photography Data Sets To Resolve Surface Structure In Areas Of Poor Exposure: Examples From Kamchatka Peninsula, Russia And Katalla Area, Alaska Usa, Sarah Natalie Heinlein
Application Of Various Remote Sensing And Aerial Photography Data Sets To Resolve Surface Structure In Areas Of Poor Exposure: Examples From Kamchatka Peninsula, Russia And Katalla Area, Alaska Usa, Sarah Natalie Heinlein
Open Access Theses & Dissertations
For many years now remote sensing data sets and application techniques of these various data have been routinely used in geological studies. Some of these studies are as basic as using Google Earth applications for general reconnaissance to more sophisticated methods for energy exploration or development of active tectonic models for a region. This dissertation presents data from two study areas within the northern pacific region utilizing a number of remote sensing and aerial photography data: 1) Kamchatka Peninsula, Russia, and 2) Katalla area of southern Alaska, USA. The Kamchatka Peninsula, Russia study evaluates surface geomorphology which includes the morphology …
Three-Dimensional Hydrostratigrapy Of The Swedeburg, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping For The Eastern Nebraska Water Resources Assessment (Enwra), Dana Divine, Jesse T. Korus
Three-Dimensional Hydrostratigrapy Of The Swedeburg, Nebraska Area: Results From Helicopter Electromagnetic (Hem) Mapping For The Eastern Nebraska Water Resources Assessment (Enwra), Dana Divine, Jesse T. Korus
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Impacts Of Predicted Global Sea-Level Rise On Oregon Beaches And Tidelands, Curt D. Peterson
Impacts Of Predicted Global Sea-Level Rise On Oregon Beaches And Tidelands, Curt D. Peterson
Geology Faculty Publications and Presentations
Forward by:
Phillip Johnson, Executive Director Oregon Shores Conservation Coalition
The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action …
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
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 …
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
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 …
Tidal Flux Of Trace Metals And Rare Earth Elements In A Barrier Island Salt Marsh, Ryan Antle
Tidal Flux Of Trace Metals And Rare Earth Elements In A Barrier Island Salt Marsh, Ryan Antle
Theses and Dissertations
Barrier island salt marshes are known as sources of nutrients to the coastal ocean but it is unclear whether they are also sources or sinks of trace metals in regards to coastal waters. Salt marshes are characterized by steep redox and biogeochemical gradients, which constantly fluctuate as a result of tidal pumping. While several studies have examined metal budgets between terrestrial fresh water, estuarine subterranean fluids, and coastal saline waters, there is little data regarding fluid chemistry for metals in salt water estuaries in the absence of fresh water input. This study investigated a back barrier salt marsh on Cabretta …
Tectonics Of The South Georgia Rift, David Michael Heffner
Tectonics Of The South Georgia Rift, David Michael Heffner
Theses and Dissertations
Triassic rifting of the supercontinent Pangea left behind numerous basins on what is now the eastern North American margin. The South Georgia Rift (SGR) was thought to be the best preserved of these basins having been capped by thick basalt flows of the Central Atlantic Magmatic Province (CAMP) and later buried beneath the Cretaceous and younger Coastal Plain. Because it is buried beneath the Coastal Plain, the SGR is only known through sparse drilling and geophysical methods. Despite this limited dataset, the SGR is the only one of the eastern North American Triassic basins known to overlie the ancient Alleghanian …
Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan
Geomechanics And Elastic Anisotropy Of The Bakken Formation, Williston Basin, Mehdi Ostadhassan
Theses and Dissertations
Many of the earth’s rocks exhibit anisotropic characteristics. Anisotropy is particularly common in many sedimentary rocks, such as shales. Anisotropy is defined as the spatial alignment of mineral grains, layers, fractures and stresses which causes elastic wave velocity and other elastic properties to vary with direction. There are two types of anisotropy: intrinsic and stress-induced. Intrinsic anisotropy is caused by beddings, microstructures or aligned fractures formed during deposition. Stress-induced anisotropy is caused by strain associated with external stresses. Intrinsic anisotropy originates in the absence of external stresses, while stress-induced anisotropy results from tectonic and overburden stresses. The style of earth …
Controlling Factors On Bedrock River Sinuosity In The Eastern Tibetan Plateau, Lydia Curliss
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
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, …
Strain Energy Release From The 2011 9.0 Mw Tōhoku Earthquake, Japan, Kenneth M. Cruikshank, Curt D. Peterson
Strain Energy Release From The 2011 9.0 Mw Tōhoku Earthquake, Japan, Kenneth M. Cruikshank, Curt D. Peterson
Geology Faculty Publications and Presentations
The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 Mw Tōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017 J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017 Nm (J). The strain energy method is independent of seismic methods for determining the energy released …
Amplitude Vs. Offset Effects On Gas Hydrates At Woolsey Mound, Gulf Of Mexico, Walter R. Anderson
Amplitude Vs. Offset Effects On Gas Hydrates At Woolsey Mound, Gulf Of Mexico, Walter R. Anderson
Theses and Dissertations
Due to the estimated massive quantities of natural methane hydrates, they represent one of the largest sources of future alternative energy on Earth. Methane hydrates have been found in the shallow sub-seafloor of the Northern Gulf of Mexico where the water depth is in excess of ~900 m. Mississippi Canyon Block 118 has been chosen by the Gulf of Mexico Hydrates Research Consortium to be the site of a multi-sensor, multi-discipline sea-floor observatory for gas hydrate research. First evidence for gas hydrates at MC 118 was observed at Woolsey Mound. Subsurface evidence for gas hydrates has subsequently been substantiated by …
Balanced Cross Section Of The Northeast Of Adiyaman, Turkey, Mustafa Tuncer
Balanced Cross Section Of The Northeast Of Adiyaman, Turkey, Mustafa Tuncer
Masters Theses
"Deformation during closure of an ocean basin and continent-continent collision in southeast Anatolia Turkey during the Late Cretaceous to Middle Miocene was investigated by construction of a geologic map, structural cross-section and retrodeformed palinspastically restored cross-section. The area of study is a N-S transect across the Bitlis Suture Zone of Northeast of Adiyaman. The study area is situated in the southeast Anatolian orogenic belt which includes, from south to north, the Arabian platform, the zone of Imbrication, and the zone of Nappes. A geologic map of this region was prepared in order to construct balanced and restored cross sections from …
3d Seismic Data Interpretation Of Boonsville Field, Texas, Aamer Ali Alhakeem
3d Seismic Data Interpretation Of Boonsville Field, Texas, Aamer Ali Alhakeem
Masters Theses
"The Boonsville field is one of the largest gas fields in the US located in the Fort Worth Basin, north central Texas. The highest potential reservoirs reside in the Bend Conglomerate deposited during the Pennsylvanian. The Boonsville data set is prepared by the Bureau of Economic Geology at the University of Texas, Austin, as part of the secondary gas recovery program. The Boonsville field seismic data set covers an area of 5.5 mi². It includes 38 wells data. The Bend Conglomerate is deposited in fluvio-deltaic transaction. It is subdivided into many genetic sequences which include depositions of sandy conglomerate representing …
A Structural Analysis Of The El Kasr Structure In The Western Desert Of Egypt, Trevor Charles Ellis
A Structural Analysis Of The El Kasr Structure In The Western Desert Of Egypt, Trevor Charles Ellis
Masters Theses
"The El Kasr structure was studied in order to investigate the origins and evolution of the enigmatic Desert Eyes structures of the Western Desert due to its accessibility and uniqueness among the structures. The El Kasr structure, an elongate structural basin with low limb dips, is unique among the "Desert Eyes" structures in that it: 1) occurs in isolation in otherwise horizontal sedimentary rock, 2) the long dimension of the basin is oriented NNW, 3) it is closely spatially associated with the less common NNW fault zones, and 4) is composite in nature. The structure was investigated using remote sensing …
Early Eocene To Middle Miocene Cooling And Aridification Of East Antarctica, Sandra Passchier, Steven M. Bohaty, Francisco J. Jiménez‐Espejo, Jörg Pross, Ursu Röhl, Tina Van De Flierdt, Carlota Escutia, Henk Brinkhuis
Early Eocene To Middle Miocene Cooling And Aridification Of East Antarctica, Sandra Passchier, Steven M. Bohaty, Francisco J. Jiménez‐Espejo, Jörg Pross, Ursu Röhl, Tina Van De Flierdt, Carlota Escutia, Henk Brinkhuis
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
[1] Few high‐latitude terrestrial records document the timing and nature of the Cenozoic “Greenhouse” to “Icehouse” transition. Here we exploit the bulk geochemistry of marine siliciclastic sediments from drill cores on Antarctica's continental margin to extract a unique semiquantitative temperature and precipitation record for Eocene to mid‐Miocene (~54–13 Ma). Alkaline elements are strongly enriched in the detrital mineral fraction in fine‐grained siliciclastic marine sediments and only occur as trace metals in the biogenic fraction. Hence, terrestrial climofunctions similar to the chemical index of alteration (CIA) can be applied to the alkaline major element geochemistry of marine sediments on continental margins …
A Study Of The Impacts Of Freeze-Thaw On Cliff Recession At The Calvert Cliffs In Calvert County, Maryland, Bonnie Elizabeth Zwissler
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
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 …
Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol
Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol
Geosciences Faculty Publications
We have conducted a series of experiments designed to investigate elastic and electromagnetic (EM) velocity anisotropy associated with a preferentially aligned fracture system on a temperate valley glacier in south-central Alaska, USA. Measurements include a three-dimensional compressional wave (P-wave) seismic reflection survey conducted over a 300 m x 300 m survey patch, with uniform source grid and static checkerboard receiver pattern. Additionally, we acquired a multiazimuth, multi-offset, polarimetric groundpenetrating radar (GPR) reflection experiment in a wagon-wheel geometry with 94 degrees of azimuthal coverage. Results show azimuthal variation in the P-wave normal-moveout velocity of less than 3% (3765 and 3630 ms …
Hydraulic Fracturing Design For Horizontal Wells In The Bakken Formation, Williston Basin, Hadi Jabbari
Hydraulic Fracturing Design For Horizontal Wells In The Bakken Formation, Williston Basin, Hadi Jabbari
Theses and Dissertations
Unconventional hydrocarbon reservoirs have proved to be challenging in terms of reservoir characterization, predicting production potential, estimating ultimate recovery, and optimizing hydraulic fracture stimulations. The methods by which these resources are extracted use progressive, or unconventional, technologies. Today, through the use of hydraulic fracturing and horizontal drilling, extraordinary amounts of oil and natural gas from deep shale formations across the United States and around the world are being safely produced.
Performing a hydraulic fracture design requires modeling of fracture propagation and tracking the fluid front in the created fracture. In this dissertation, the roles of all effective parameters and properties …
Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides
Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides
Open Access Theses & Dissertations
Ca is a trace element in olivine and its concentration is pressure and temperature dependent, providing a rare opportunity to estimate pressure conditions at which mantle-derived rocks (xenoliths) last equilibrated. This P-T dependence has previously been calibrated for mantle xenoliths, and we applied this technique to samples from Jasper Seamount (Jasper Seamount), an oceanic intraplate volcano (OIV) off the coast of the Baja California Peninsula of Mexico. Preliminary compositions for xenoliths from this location appear to define a magmatic plumbing system that features magma storage near the bottom of the crust. A more detailed analysis of the samples is required …