Geophysics and Seismology Commons^™

An Investigation Into The Origin, Composition, And Commercial Significance Of A Sedimentary Subsalt Formation: Keathley Canyon, Gulf Of Mexico, David Aaron Brassieur

University of New Orleans Theses and Dissertations

Sub-salt oil and gas formations in deep-water northern Gulf of Mexico are high priority targets. Advances in seismic processing allow for high-resolution, below-salt imaging. Understanding the modes of salt emplacement provide insight into sub-salt traps and potential drilling hazards.

A sub-salt sedimentary unit lies in the Keathley Canyon protraction. Autosutures created the transport-parallel lineaments of the upper surface of the unit. In addition, highly variable sediment aggradation rates created ramps, flats, and basal cutoffs along the base of the allochthon as salt and sediment competed for space. Seismic models identify modes of salt emplacement, salt/sediment interactions, and mechanisms responsible for …

Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook

Electronic Theses and Dissertations

This dissertation is concerned with the development of robust numerical solution procedures for the generalized micromechanical analysis of linear and nonlinear constitutive behavior in heterogeneous materials. Although the methods developed are applicable in many engineering, geological, and materials science fields, three main areas are explored in this work. First, a numerical methodology is presented for the thermomechanical analysis of heterogeneous materials with a special focus on real polycrystalline microstructures obtained using electron backscatter diffraction techniques. Asymptotic expansion homogenization and finite element analysis are employed for micromechanical analysis of polycrystalline materials. Effective thermoelastic properties of polycrystalline materials are determined and compared …

Hydrocode Modeling Of Oblique Impacts Into Terrestrial Planets, Jordan D. Kendall

Open Access Dissertations

The abundance of moderately siderophile elements (“iron-loving”; e.g., Co, Ni) in the Earth’s mantle is 10 to 100 times larger than predicted by chemical equilibrium between silicate melt and iron at low pressure, but it does match expectation for equilibrium at high pressure and temperature. Recent studies of differentiated planetesimal impacts assume that planetesimal cores survive the impact intact as concentrated masses that passively settle from a zero initial velocity and undergo turbulent entrainment in a global magma ocean; under these conditions, cores greater than 10 km in diameter do not fully mix without a sufficiently deep magma ocean. I …

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas. 2D …

Facies Reconstruction And Stratigraphy Of A Late Pleistocene Bald Cypress Forest Discovered On The Northern Gulf Of Mexico Continental Shelf, Suyapa Gonzalez-Rodriguez

Honors Theses

No abstract provided.

Facies Reconstruction And Stratigraphy Of A Late Pleistocene Bald Cypress Forest Discovered On The Northern Gulf Of Mexico Continental Shelf, Suyapa Gonzalez

Honors Theses

No abstract provided.

Miocene Contourite Deposition (Along-Slope) Near Desoto Canyon, Gulf Of Mexico: A Product Of An Enhanced Paleo-Loop Current, Shane Christopher Dunn

USF Tampa Graduate Theses and Dissertations

A Neogene contourite depositional system was identified and mapped along the DeSoto Slope in the northeastern Gulf of Mexico, U.S.A. A series of drift deposits comprising the larger contourite depositional system were interpreted from a 2-D industry seismic data set. The now subsurface drift deposits are adjacent to the anomalous seabed feature, the DeSoto Canyon, and these data suggest contourite deposition and ocean currents are in integral part of the canyon’s depositional history. The contourite depositional system is underlain by an extensive, middle Miocene aged, erosional unconformity formed by ocean currents. The timing of this erosional surface is in alignment …

Modeling The Thickness Of Perennial Ice Covers On Stratified Lakes Of The Taylor Valley, Antarctica, Maciej K. Obryk, Peter T. Doran, Jared A. Hicks, Christopher P. Mckay, John Charles Priscu

Geology Faculty Publications and Presentations

A 1-D ice cover model was developed to predict and constrain drivers of long-term ice thick-ness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface ra-diative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 a (between 1996 and 2012) of ice thickness changes for the west lobe of Lake Bonney (average ice thickness = 3.53 m) and Lake Fryxell (average ice thickness = 4.22 m). Long-term ice thick-ness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of …

The Application Of Geophysical Inversion Techniques To The Nechalacho Rare Earth Element Deposit, Nt, Derek W. Kouhi

Electronic Thesis and Dissertation Repository

The Nechalacho deposit is a world-class rare earth element deposit located in the Thor Lake region approximately 100 kilometers southwest of Yellowknife, NT, Canada. Located within the Blatchford Lake Intrusion Complex, this deposit has the potential to be a large-scale economic asset due to its relatively shallow and sub-horizontal geometry. In this study, geophysical inversion techniques are used to model subsurface magnetic susceptibility and density in order to delineate the deposit. Isolated and joint inversion of both magnetic and gravity data provides similar models. Each inversion procedure delineates a shallow, sub-horizontal layer of high susceptibility and density in approximately the …

Geologic, Geochemical, And Geophysical Characterization Of The Gold Deposits Of The Horseshoe Bend Mining District, Idaho: Building A Four Dimensional Model For Ore Exploration, Joshua Ekhoff

Boise State University Theses and Dissertations

The Eocene aged Trans-Challis Fault System of central Idaho provides the tectonic and magmatic framework for a series of Au-Ag and Cu-Mo ore deposits. From its northernmost extension near Butte, Montana to its southwestern terminus in the Boise Basin of south-central Idaho the Trans-Challis Fault System is associated with some of the richest precious metal deposits found in Idaho. However, the southernmost tip of the Trans-Challis Fault System, composed of the Horseshoe Bend and Pearl mining districts, remains understudied, receiving little economic or academic attention. As a result, how the Pearl to Horseshoe Bend mining districts fit within the established …

An Evaluation Of Paleomagnetic Techniques To Determine Emplacement Temperatures Of Pyroclastic Density Currents At Mount St. Helens, Devin Gerzich

Theses and Dissertations

During a volcanic eruption, pyroclastic density currents (PDCs) deposit new pumice and ash and rip out and transport lithic fragments from past eruptions. Magnetic minerals in the lithic fragments, such as titanomagnetite, may be partially or completely remagnetized, depending on their emplacement temperature with respect to their Curie and blocking temperatures. By finding the temperature at which this remagnetized overprint is removed, the emplacement temperature of the pyroclastic flow is estimated. This method assumes that the rock magnetic properties that govern magnetic unblocking are constant given a specific magnetic mineral composition, but recent studies demonstrate that Curie temperatures (Tc) in …

Implications For The North American Lower Crustal 7.Xx Km/S Layer From An Exhumed Crustal Root, Western Canadian Shield, Calvin Everette Johnson

Graduate Theses and Dissertations

Studies of the Thorsby magnetic low, the southern extent of the 2,800 km-long Snowbird

Tectonic Zone (STZ) in Alberta, Canada, show pronounced lower crustal seismic reflectivity and preservation of a crustal root. These features may be correlative to the well-exposed central STZ, where two lower crustal tectonic events have been identified at 2.6-2.55 Ga and 1.92-1.89 Ga. High-resolution cross-sections of the central STZ reveal the late-stage interaction of Paleoproterozoic intracontinental thrust and strike-slip shear zones responsible for juxtaposing ca. >20,000 km2 of lower continental crust (0.9-1.5 GPa) with middle continental crust (0.5 GPa) (Mahan and Williams, 2005; Dumond et al., …

3d Seismic Interpretation Of Paleokarst Sinkholes, Boone Limestone, Lower Mississippian: Subsurface Eastern Arkoma Basin, Conway County, Arkansas, Daniel James Moser

Graduate Theses and Dissertations

Unconventional natural gas discoveries in the Fayetteville Shale of the eastern Arkoma Basin have led to improved understanding of subsurface geology in central Arkansas. This study interprets 3D seismic data for evidence of paleokarst within the Mississippian formations in a portion of the subsurface of Conway County, Arkansas. Quantitative data interpretation suggests that sinkholes developed during the Mississippian portion of the eastern Arkoma Basin record.

In a nine square mile area, 3D seismic mapping of Mississippian formations show 14 closed depressions interpreted as karst sinkholes. Time and depth structure maps were created and utilized to estimate the timing of dissolution …

Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington

July 29, 2016: The Latest in Sea Level Rise Science

No abstract provided.

2015 Gsa International Distinguished Lecturer Tours Key Locations In Central And South America, Lisa L. Ely

Geological Sciences Faculty Scholarship

As the International Lecturer from North America, I visited 11 destinations in Ecuador, Peru, Chile, Costa Rica, Mexico, and Puerto Rico. The tour was designed to include locations where the topic of my presentation, “Following in the Footsteps of Darwin:
Combining Geological and Historical Evidence to Assess Earthquakes and Tsunami Hazards,” would have direct relevance.

The Influence Of The Great Falls Tectonic Zone On The Thrust Sheet Geometry Of The Southern Sawtooth Range, Montana, Usa, Caroline M. Burberry, J. M. Palu

Department of Earth and Atmospheric Sciences: Faculty Publications

The reactivation potential of pre-existing deep-seated structures influences deformation structures produced in subsequent compression. This contribution investigates thrust geometries produced in surface thrust sheets of the Sawtooth Range, Montana, USA, deforming over a previously faulted sedimentary section. Surface thrust fault patterns were picked using existing maps and remote sensing. Thrust location and regional transport direction was also verified in the field. These observations were used to design a series of analogue models, involving deformation of a brittle cover sequence over a lower section with varying numbers of vertical faults. A final model tested the effect of decoupling the upper cover …

Surface Slip During Large Owens Valley Fault Earthquakes, Elizabeth K. Haddon, Colin B. Amos, O. Zielke, A. S. Jayko, R. Bürgmann

Geology Faculty Publications

The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross‐correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) …

Seismic Array Studies Of Antarctica And Madagascar, Martin James Pratt

Arts & Sciences Electronic Theses and Dissertations

The scope of this dissertation is broad, involving seismic array studies from Antarctica and Madagascar, and includes aspects of glaciology and oceanography as well as solid Earth geophysics. Chapter 2 focuses on the study of stickslip motion of the Whillans Ice Stream, West Antarctica. It includes methods combining seismic array and GPS time series, from ice stream based-sensors, to determine source dynamics in the framework of an earthquake source. The source characteristics are then analyzed to explain far-field seismic observations of ice stream- sourced surface waves detected throughout West Antarctica. Locations of asperities, or sticky- spots, that cause the Whillans …

Search For An Artificially Buried Karst Cave Entrance Using Ground Penetrating Radar: A Successful Case Of Locating The S-19 Cave In The Mt. Kanin Massif (Nw Slovenia), Andrej Gosar, Teja Čeru

International Journal of Speleology

The S-19 Cave was with its explored depth of 177 m one of the most important caves of the Mt. Kanin massif, but after its discovery in 1974, a huge snow avalanche protection dyke was constructed across the cave entrance. To excavate the buried cave, the accurate location of the cave had to be determined first. Since the entrance coordinates were incorrect and no markers were available, application of geophysical techniques was necessary to do this. A Ground Penetrating Radar (GPR) with special 50 MHz rough terrain antennas was selected as the single suitable geophysical method for the given conditions …

Stratigraphic Interpretation And Reservoir Implications Of The Arbuckle Group (Cambrian-Ordovician) Using 3d Seismic, Osage County, Oklahoma, Ryan Marc Keeling

Graduate Theses and Dissertations

The Arbuckle Group in northeastern Oklahoma consists of multiple carbonate formations, along with several relatively thin sandstone units. The group is a part of the “Great American Carbonate Bank” of the mid-continent and can be found regionally as far east as the Arkoma Basin in Arkansas, and as far west as the Anadarko Basin in Oklahoma. The Arbuckle is part of the craton-wide Sauk sequence, which is both underlain and overlain by regional unconformities.

Arbuckle is not deposited directly on top of a source rock. In order for reservoirs within the Arbuckle to become charged with hydrocarbons, they must be …

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Shuang-ye Wu

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Shuang-ye Wu

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland

Allen J. McGrew

New mapping, structural analysis, and 40Ar/39Ar dating reveal an unusually well‐constrained history of Late Eocene extension in the Copper Mountains of the northern Basin and Range province. In this area, the northeast‐trending Copper Creek normal fault juxtaposes a distinctive sequence of metacarbonate and granitoid rocks against a footwall of Upper Precambrian to Lower Cambrian quartzite and phyllite. Correlation of the hanging wall with footwall rocks to the northwest provides an approximate piercing point that requires 8–12 km displacement in an ESE direction. This displaced fault slice is itself bounded above by another normal fault (the Meadow Fork Fault), which brings …

Mass Density At Geostationary Orbit And Apparent Mass Refilling, Richard Denton, Kazue Takahashi, Justice Amoh, J. Singer

Dartmouth Scholarship

We used the inferred equatorial mass density rho_{m,eq} based on measurements of Alfven wave frequencies measured by the GOES satellites during 1980--1991 in order to construct a number of different models of varying complexity for the equatorial mass density at geostationary orbit. The most complicated models are able to account for 66% of the variance with a typical variation from actual values of a factor of 1.56. The factors that influenced rho_{m,eq} in the models were, in order of decreasing importance, the F10.7 EUV index, magnetic local time, MLT, the solar wind dynamic pressure P_{dyn}, the phase of the year, …

Gps Constraints On Interplate Locking Within The Makran Subduction Zone, Elyse Frohling, Walter Szeliga

All Faculty Scholarship for the College of the Sciences

The Makran subduction zone is one of the last convergent margins to be investigated using space-based geodesy. While there is a lack of historical and modern instrumentation in the region, a sparse sampling of continuous and campaign measurements over the past decade has allowed us to make the first estimates of convergence rates. We combine GPS measurements from 20 stations located in Iran, Pakistan and Oman along with hypocentral locations from the International Seismological Centre to create a preliminary 3-D estimate of the geometry of the megathrust, along with a preliminary fault-coupling model for the Makran subduction zone. Using a …

Stratigraphic Analysis Of Florissant Fossil Beds National Monument Using Magnetic Susceptibility, Geochemical Comparison, And Gamma Ray Spectroscopy, Jennifer Kenyon

Honors Theses

No abstract provided.

Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin

Open Access Dissertations

The US agriculture system is the world’s largest producer of maize and soybean, and typically supplies more than one-third of their global trading. Nearly 90% of the US maize and soybean production is rainfed, thus is susceptible to climate change stressors such as heat waves and droughts. Process-based crop and cropping system models are important tools for climate change impact assessments and risk management. As data- science is becoming a new frontier for agriculture growth, the incoming decade calls for operational platforms that use hyper-local growth monitoring, high-resolution real-time weather and satellite data assimilation and cropping system modeling to help …

Present Day Plate Boundary Deformation In The Caribbean And Crustal Deformation On Southern Haiti, Steeve Symithe

Open Access Dissertations

The Caribbean plate and its boundaries with North and South America, marked by subduction and large intra-arc strike-slip faults, are a natural laboratory for the study of strain partitioning and interseismic plate coupling in relation to large earth- quakes. In this work, I use the available campaign and continuous GPS measurements in the Caribbean to derive a regional velocity field expressed in a consistent reference frame. I use this velocity field as input to a kinematic model where surface velocities result from the rotation of rigid blocks bounded by locked faults accumulating inter- seismic strain, while allowing for partial locking …

Reservoir Study And Facies Analysis Of The Big Clifty Sandstone In South Central Kentucky, Tyler S. Bodine

Masters Theses & Specialist Projects

The Big Clifty (Jackson) Sandstone Member of the Golconda Formation is the most important of the Mississippian (Chesterian) heavy-oil reservoirs in the southeastern Illinois Basin. Heavy oil reservoirs, or asphalt rock deposits, have been studied extensively in south central and western Kentucky, and ~2 billion barrels of original oil in place (OOIP) have been proposed to occur in the Big Clifty Sandstone. Despite high OOIP estimates, heterogeneities in the reservoir negatively impact the production of heavy oil deposits. Heterogeneities related to depositional facies changes are poorly understood in the Big Clifty Sandstone of Kentucky, where it has been mostly described …

Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar

Umesh K. Haritashya

Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than that at night-time. The average daytime and …