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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 ...


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 ...


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

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.


Explosive Dome Eruptions Modulated By Periodic Gas-Driven Inflation, Jeffrey B. Johnson, J. J. Lyons, B. J. Andrews, J. M. Lees 2016 Boise State University

Explosive Dome Eruptions Modulated By Periodic Gas-Driven Inflation, Jeffrey B. Johnson, J. J. Lyons, B. J. Andrews, J. M. Lees

Jeffrey Lyons

Volcan Santiaguito (Guatemala) “breathes” with extraordinary regularity as the edifice's conduit system accumulates free gas, which periodically vents to the atmosphere. Periodic pressurization controls explosion timing, which nearly always occurs at peak inflation, as detected with tiltmeters. Tilt cycles in January 2012 reveal regular 26 ± 6 min inflation/deflation cycles corresponding to at least ~101 kg/s of gas fluxing the system. Very long period (VLP) earthquakes presage explosions and occur during cycles when inflation rates are most rapid. VLPs locate ~300 m below the vent and indicate mobilization of volatiles, which ascend at ~50 m/s. Rapid gas ...


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 2016 Portland State University

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 ...


A Modified Delay-Time Method For Statics Estimation With The Virtual Refraction, T. Dylan Mikesell, Kasper van Wijk, Elmer Ruigrok, Andrew Lamb, Thomas E. Blum 2016 Boise State University

A Modified Delay-Time Method For Statics Estimation With The Virtual Refraction, T. Dylan Mikesell, Kasper Van Wijk, Elmer Ruigrok, Andrew Lamb, Thomas E. Blum

Dylan Mikesell

Topography and near-surface heterogeneities lead to traveltime perturbations in surface land-seismic experiments. Usually, these perturbations are estimated and removed prior to further processing of the data. A common technique to estimate these perturbations is the delay-time method. We have developed the “modified delay-time method,” wherein we isolate the arrival times of the virtual refraction and estimate receiver-side delay times. The virtual refraction is a spurious arrival found in wavefields estimated by seismic interferometry. The new method removes the source term from the delay-time equation, is more robust in the presence of noise, and extends the lateral aperture compared to the ...


Monitoring Southwest Greenland’S Ice Sheet Melt With Ambient Seismic Noise, Aurélien Mordret, T. Dylan Mikesell, Christopher Harig, Bradley P. Lipovsky, Germán A. Prieto 2016 Massachusetts Institute of Technology

Monitoring Southwest Greenland’S Ice Sheet Melt With Ambient Seismic Noise, Aurélien Mordret, T. Dylan Mikesell, Christopher Harig, Bradley P. Lipovsky, Germán A. Prieto

Dylan Mikesell

The Greenland ice sheet presently accounts for ~70% of global ice sheet mass loss. Because this mass loss is associated with sea-level rise at a rate of 0.7 mm/year, the development of improved monitoring techniques to observe ongoing changes in ice sheet mass balance is of paramount concern. Spaceborne mass balance techniques are commonly used; however, they are inadequate for many purposes because of their low spatial and/or temporal resolution. We demonstrate that small variations in seismic wave speed in Earth’s crust, as measured with the correlation of seismic noise, may be used to infer seasonal ...


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