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An Investigation Into The Origin, Composition, And Commercial Significance Of A Sedimentary Subsalt Formation: Keathley Canyon, Gulf Of Mexico, David Aaron Brassieur 2016 University of New Orleans, New Orleans

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 ...


Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub 2016 Stephen F Austin State University

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 ...


Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook 2016 University of Maine

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 ...


Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen 2016 Western Washington University

Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen

Bernard A. Housen

Viscous remanent magnetization (VRM) may partially overprint original magnetization in rocks displaced by geomorphic events. An established theoretical relationship between the time and temperature of acquisition of VRM and the time and temperature of demagnetization suggests that laboratory demagnetization (unblocking) of VRM can be used to estimate the displacement age of rocks. We test this hypothesis at four nested glacial moraines in the Icicle Creek drainage of central Washington, the ages of which were previously determined by cosmogenic surface exposure dating. The moraines are composed primarily of granodiorite boulders, and magnetic remanence is carried dominantly by magnetite. Both the maximum ...


Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen 2016 Western Washington University

Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen

Russ R. Burmester

Viscous remanent magnetization (VRM) may partially overprint original magnetization in rocks displaced by geomorphic events. An established theoretical relationship between the time and temperature of acquisition of VRM and the time and temperature of demagnetization suggests that laboratory demagnetization (unblocking) of VRM can be used to estimate the displacement age of rocks. We test this hypothesis at four nested glacial moraines in the Icicle Creek drainage of central Washington, the ages of which were previously determined by cosmogenic surface exposure dating. The moraines are composed primarily of granodiorite boulders, and magnetic remanence is carried dominantly by magnetite. Both the maximum ...


Paleomagnetism Of The Patagonian Plateau Basalts, Southern Chile And Argentina, Robert F. Butler, Francisco Herve, Francisco Munizaga, Myurl E. Beck Jr., Russell F. Burmester, Eduardo S. Oviedo 2016 University of Portland

Paleomagnetism Of The Patagonian Plateau Basalts, Southern Chile And Argentina, Robert F. Butler, Francisco Herve, Francisco Munizaga, Myurl E. Beck Jr., Russell F. Burmester, Eduardo S. Oviedo

Russ R. Burmester

A total of 505 paleomagnetic samples were collected from 65 sites (volcanic flows) of the Patagonian plateau basalts at four locations in southern Chile and Argentina. K/Ar analyses indicate that 38 flows from two locations form a Late Cretaceous group (64–79 Ma), while the remaining 27 flows are Eocene in age (42–56 Ma). Progressive demagnetization indicates that a characteristic remanent magnetization (ChRM) has been successfully isolated from 59 flows. Rock-magnetic properties and analysis of ChRM directions within and between sites allow the secure inference that the ChRM is a thermoremanent magnetization acquired during original cooling. The Eocene ...


The Hydrogeologic Information In Cross-Borehole Complex Conductivity Data From An Unconsolidated Conglomeratic Sedimentary Aquifer, Andrew Binley, John Keery, Lee Slater, Warren Barrash, Mike Cardiff 2016 Lancaster University

The Hydrogeologic Information In Cross-Borehole Complex Conductivity Data From An Unconsolidated Conglomeratic Sedimentary Aquifer, Andrew Binley, John Keery, Lee Slater, Warren Barrash, Mike Cardiff

Warren Barrash

Accurate estimation of the hydrological properties of near-surface aquifers is important because these properties strongly influence groundwater flow and solute transport. Laboratory-based investigations have indicated that induced polarization (IP) properties of porous media may be linked, through either semi-empirical or fully mechanistic models, to hydrological properties including hydraulic conductivity. Therefore, there is a need for field assessments of the value of IP measurements in providing insights into the hydrological properties of aquifers. A cross-borehole IP survey was carried out at the Boise Hydrogeophysical Research Site (BHRS), an unconsolidated fluvial aquifer that has previously been well-studied with a variety of geophysical ...


Re-Assessment Of Lithostratigraphy, Biostratigraphy, And Volcanic Activity Of The Late Paleozoic Intra-Sudetic, Krkonoše-Piedmont And Mnichovo Hradiště Basins (Czech Republic) Based On New U-Pb Ca-Id-Tims Ages, Stanislav Opluštil, Mark Schmitz, Václav Kachlík, Stanislav Štamberg 2016 Charles University in Prague

Re-Assessment Of Lithostratigraphy, Biostratigraphy, And Volcanic Activity Of The Late Paleozoic Intra-Sudetic, Krkonoše-Piedmont And Mnichovo Hradiště Basins (Czech Republic) Based On New U-Pb Ca-Id-Tims Ages, Stanislav Opluštil, Mark Schmitz, Václav Kachlík, Stanislav Štamberg

Mark D. Schmitz

Five U-Pb CA-ID-TIMS high-precision ages were obtained from single zircon crystals separated from tuffs or ignimbrites embedded in Pennsylvanian to Asselian sediments of the Intra-Sudetic, Krkonoše-Piedmont and the adjacent part of the Mnichovo Hradiště basins. The new radioisotopic data are used for extrapolation of ages of dated lithostratigraphic units. The existing borehole network in the Late Paleozoic continental basins of central and western Bohemia and in the Sudetic area, and similarity of their stratigraphically equivalent strata including some common lacustrine horizons allow a detailed lithostratigraphical correlation between these two areas. This in turn, allows combining our new radioisotopic data with ...


The Application Of Geophysical Inversion Techniques To The Nechalacho Rare Earth Element Deposit, Nt, Derek W. Kouhi 2016 The University of Western Ontario

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 ...


The Geophysical Kitchen Sink Approach To Improving Our Understanding Of Volcano-Tectonic Interactions, Ophelia Ann George 2016 University of South Florida

The Geophysical Kitchen Sink Approach To Improving Our Understanding Of Volcano-Tectonic Interactions, Ophelia Ann George

Graduate Theses and Dissertations

A multi-prong approach was taken in this dissertation to understand volcanic processes from both a long-term and more immediate hazard perspective. In the long-term, magma sources within the crust may produce measurable surficial response and long-wavelength gravity anomalies that provide information about the extent and depth of this magma. Long-term volcanic hazard forecasting is also improved by developing as complete a record as possible of past events. In the short-term, a long-standing question has been on the casting of precursory volcanic activity in terms of future volcanic hazards. Three studies are presented in this dissertation to address these issues. Inversion ...


Mineral Physics Modeling Of The Effect Of Water On Crustal Seismic Velocity Ratios, Eric Lyman 2016 Utah State University

Mineral Physics Modeling Of The Effect Of Water On Crustal Seismic Velocity Ratios, Eric Lyman

Physics Capstone Project

This research explores the relationship between the presence of water (H2O) in the make up of rocks and minerals (specifically quartz) at different levels in the crust. The relationships were calculated using Perple_x software to adjust the level of the different chemical and mineral make up of the rock. The densities were calculated using the velocity of primary waves and shear waves as collected by Tony Lowry. There seems to be at least a casual link between water content and quartz content.


Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels 2016 Boise State University

Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels

Geosciences Faculty Publications and Presentations

Estimates of S-wave velocity with depth from Rayleigh-wave dispersion data are limited by the accuracy of fundamental and/or higher mode signal identification. In many scenarios, the fundamental mode propagates in retrograde motion, whereas higher modes propagate in prograde motion. This difference in particle motion (or polarity) can be used by joint analysis of vertical and horizontal inline recordings. We have developed a novel method that isolates modes by separating prograde and retrograde motions; we call this a polarity mute. Applying this polarity mute prior to traditional multichannel analysis of surface wave (MASW) analysis improves phase velocity estimation for fundamental ...


Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels 2016 Boise State University

Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels

Dylan Mikesell

Estimates of S-wave velocity with depth from Rayleigh-wave dispersion data are limited by the accuracy of fundamental and/or higher mode signal identification. In many scenarios, the fundamental mode propagates in retrograde motion, whereas higher modes propagate in prograde motion. This difference in particle motion (or polarity) can be used by joint analysis of vertical and horizontal inline recordings. We have developed a novel method that isolates modes by separating prograde and retrograde motions; we call this a polarity mute. Applying this polarity mute prior to traditional multichannel analysis of surface wave (MASW) analysis improves phase velocity estimation for fundamental ...


Using Physical And Social Sensors In Real-Time Data Streaming For Natural Hazard Monitoring And Response, Yelena Kropivnitskaya 2016 The University of Western Ontario

Using Physical And Social Sensors In Real-Time Data Streaming For Natural Hazard Monitoring And Response, Yelena Kropivnitskaya

Electronic Thesis and Dissertation Repository

Technological breakthroughs in computing over the last few decades have resulted in important advances in natural hazards analysis. In particular, integration of a wide variety of information sources, including observations from spatially-referenced physical sensors and new social media sources, enables better estimates of real-time hazard. The main goal of this work is to utilize innovative streaming algorithms for improved real-time seismic hazard analysis by integrating different data sources and processing tools into cloud applications. In streaming algorithms, a sequence of items from physical and social sensors can be processed in as little as one pass with no need to store ...


Anisotropic Waveform Tomography: Application To Crosshole Data For Transversely Isotropic Media, Shaun Michael Hadden 2016 The University of Western Ontario

Anisotropic Waveform Tomography: Application To Crosshole Data For Transversely Isotropic Media, Shaun Michael Hadden

Electronic Thesis and Dissertation Repository

Anisotropic Traveltime Tomography and Full Waveform Inversion were applied first to synthetic and then to real data following the development of a transversely isotropic model for handling anisotropy. Best-fitting models of seismic velocity and Thomsen's anisotropy parameters were initially obtained from traveltime tomography, and then used as the starting models for Full Waveform Inversion. The use of a Laplace transform approach effectively damps late arriving S-wave artifacts that introduce errors into the modelling process. The results of the synthetic study highlights the tradeoffs in resolution between the two parameter classes, but verify anisotropic traveltime tomography as a valid method ...


Particle Swarm Transport In Porous Media, Alison R. Hoe, Laura J Pyrak-Nolte 2016 Purdue University

Particle Swarm Transport In Porous Media, Alison R. Hoe, Laura J Pyrak-Nolte

The Summer Undergraduate Research Fellowship (SURF) Symposium

In recent years, interest in particulate transport in the subsurface has increased with the increased use of micro-particulates in consumer products. In this research, we study particulate swarm transport through porous media that depends on the complexity of the flow paths, on the size and shape of the particles and on the physical interactions among the particles, fluids, and matrix. Specifically, we investigate the effect of pore geometry and grain wettability on swarm evolution under gravity. Swarms were composed of 3 micron polystyrene beads in either water or water with KCL (%). Two types of grains are used to simulate a ...


Lava Lake Eruptive Processes Quantified With Infrasound And Video At Mount Erebus, Antarctica, Alexander Miller 2016 Boise State University

Lava Lake Eruptive Processes Quantified With Infrasound And Video At Mount Erebus, Antarctica, Alexander Miller

Boise State University Theses and Dissertations

A natural laboratory exists at Mount Erebus where strombolian activity from the lava lake is directly observed from the crater rim. Lava lake eruptions occur when pressurized bubble slugs distend the lake surface before bursting within a few tenths of a second. The unique setting presents an ideal site to quantify bubble growth through infrasound and video analysis. Two infrasound sensors and one video camera recorded eruptions ~330 m from the lava lake in 2006. Infrasound waveforms exhibit a high-amplitude bipolar pulse followed by a coda consisting of about five decaying oscillations. Video records are quantified by tracking the expanding ...


An Evaluation Of Paleomagnetic Techniques To Determine Emplacement Temperatures Of Pyroclastic Density Currents At Mount St. Helens, Devin Gerzich 2016 University of Wisconsin-Milwaukee

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 ...


Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington 2016 Old Dominion University

Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington

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

No abstract provided.


Discipline-Based Planetary Education Research And Computational Fluid Dynamics Analysis Of Mars, Filis Coba 2016 Old Dominion University

Discipline-Based Planetary Education Research And Computational Fluid Dynamics Analysis Of Mars, Filis Coba

Physics Theses & Dissertations

This thesis originates from the testing and implementation of an IRB-approved interactive animation designed to help students understand what causes The Reasons For The Seasons (RFTS) on Earth. Results from the testing indicated a small improvement in student understanding after exposure to the animation. Next, using the 3-D mapping tool Google Earth, students explored seasons and other planetary features on Mercury, Venus, the Moon and Mars through IRB-approved interactive tours which were developed and tested for astronomy education. Results from the tests indicated that there were statistically significant learning gains (p-value < 0.05) after students interacted with the tours compared to those who did not. The development of the tours inspired a geophysics study of the possibility of former plate motion (or plate tectonics) on Mars. A 2-D finite element convection model for the mantle of Mars was designed and solved using COMSOL Multiphysics 5.1, to investigate whether or not thermal gradients in a Mars-sized planet could cause vigorous upper mantle convection, consistent with plate tectonic processes. Results from this project indicated that stable convection could occur in the interior of a Mars-like planet assuming the presence of sufficiently high thermal gradients at about 0.8 times the mantle temperature of Earth. The convective patterns resembled hot upwelling and cool downwelling which may be similar to subduction-like features. Furthermore, increasing the temperature of the hot boundaries resulted in faster, more rigorous convective motions and a hotter average temperature.


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