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Tracking And Characterization Of Moving Acoustic Sources Using An Infrasound Array At Volcán Santiaguito, Guatemala, Brian R. Terbush 2015 Boise State University

Tracking And Characterization Of Moving Acoustic Sources Using An Infrasound Array At Volcán Santiaguito, Guatemala, Brian R. Terbush

Boise State University Theses and Dissertations

Active volcanic processes produce large amounts of acoustic energy within the infrasound band (0-20 Hz). Infrasound-sensitive microphones are often installed in addition to other forms of volcano monitoring equipment to increase the ability to remotely detect volcanic activity. In this study, an array of microphones was deployed without any additional sensor types for 36 hours at Santiaguito, Guatemala, to test the detection capabilities of a standalone microphone array. Array processing was applied to the recorded data, through frequency-domain beamforming and calculating a Fisher statistic (F). A changing F-threshold value was applied to differentiate between desired detections, or …


Defining Antecedent Topography At Coral Pink Sand Dunes, Kane County, Utah: The Influence Of Structural Controls On Dune-Field Boundary Conditions And Holocene Landscape Evolution, Elizabeth Janna Rozar 2015 Boise State University

Defining Antecedent Topography At Coral Pink Sand Dunes, Kane County, Utah: The Influence Of Structural Controls On Dune-Field Boundary Conditions And Holocene Landscape Evolution, Elizabeth Janna Rozar

Boise State University Theses and Dissertations

Dune fields are transient features that record climate signatures through changes in mobility, morphology, and patterning. Aeolian geomorphologists are increasingly recognizing the important role that pre-existing, antecedent topography plays in controlling boundary conditions that affect changes in dune patterning. However, the dynamic relationship between antecedent topography and climate-sensitive boundary conditions is relatively unexplored. Here, I define antecedent topography for the Coral Pink Sand Dunes in southern Utah and show that structural controls play an important role in shaping antecedent geomorphic conditions of this dune field. I use ground-based terrestrial laser scanning (TLS) to produce a high-resolution digital elevation model (DEM), …


Multi-Component Active Source Rayleigh Wave Analysis, Gabriel Gribler 2015 Boise State University

Multi-Component Active Source Rayleigh Wave Analysis, Gabriel Gribler

Boise State University Theses and Dissertations

Determining how a building site will respond to earthquake ground shaking plays a critical role in proper construction practices. One critical constraint on how a site responds is the near surface shear wave seismic velocity distribution. One commonly used method for indirectly estimating shear wave velocities is Multichannel Analysis of Surface Waves (MASW), which utilizes a spread of vertical geophones to measure Rayleigh wave dispersion. With this approach, phase velocity vs. frequency dispersion curve picks can be used to estimate shear wave velocities with depth. I investigate the use of two (vertical and horizontal inline) component seismic signals to record …


Recent Seismicity And Regional Extension Aithin Southwestern Montana, Usa, Jessica Szkody 2015 Western Michigan University

Recent Seismicity And Regional Extension Aithin Southwestern Montana, Usa, Jessica Szkody

Masters Theses

Southwestern Montana has experienced several large damaging earthquakes over the last 100 years, but many minor ones that unveil the nature of the intraplate seismicity. The region in this study is part of two distinct Late Cretaceous tectonic provinces, the Rocky Mountain Foreland Basement (RMFB) and the Cordilleran Fold and Thrust Belt (CFTB). Relationships between the two provinces and their faults show that the focal mechanisms are different. Deep focal mechanisms (between 8 and 10 km) within the RMFB can be placed on a specific fault, with many smaller events falling within the hanging wall. The hypocenters within the hanging …


Automatic Detection And Denoising Of Signals In Large Geophysical Datasets, Gabriel O. Trisca 2015 Boise State University

Automatic Detection And Denoising Of Signals In Large Geophysical Datasets, Gabriel O. Trisca

Boise State University Theses and Dissertations

To fully understand the complex interactions of various phenomena in the natural world, scientific disciplines such as geology and seismology increasingly rely upon analyzing large amounts of observations. However, data collection is growing at a faster rate than what is currently possible to analyze through traditional approaches. These datasets, supplied by the increasing use of sensors and remote sensing, require specialized computer programs to effectively analyze complex and expansive volumes of data.

Elaborating on existing geophysical data processing approaches for infrasound data collected from an avalanche-prone area, this project proposes new techniques for processing large geophysical datasets. These improved techniques …


Forecasting The Response Of Earth’S Surface To Future Climatic And Land Use Changes: A Review Of Methods And Research Needs, Jennifer L. Pierce, Michael J. Poulos 2015 Boise State University

Forecasting The Response Of Earth’S Surface To Future Climatic And Land Use Changes: A Review Of Methods And Research Needs, Jennifer L. Pierce, Michael J. Poulos

Geosciences Faculty Publications and Presentations

In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now have gridded global forecasts, being continually improved, of the climatic and land use changes (C&LUC) that are likely to occur in the coming decades. However, besides a few exceptions, consensus forecasts do not exist for how these C&LUC will likely impact Earth-surface processes and hazards. In some cases, we have …


Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson 2015 Montana Tech of the University of Montana

Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson

Graduate Theses & Non-Theses

The stable isotopic compositions of over 90 hydrothermal carbonate minerals in the Butte porphyry-lode system were analyzed. These samples came from the underground workings as well as the active Continental Pit area. Most material came from polymetallic “Main Stage” veins which post-date the porphyry Cu-Mo mineralization of Butte. Some samples from late calcite-stellerite veins were also included in the study. Rhodochrosite d13C and d18O values range from -8.3 to -2.9‰ (average of -6.7±1.0‰) and -1.8 to 12.8‰ (average of 3.6 ±3.4‰) respectively, while calcite d13C and d18O values range from -9.0 to …


Resonance Of Relativistic Electrons With Electromagnetic Ion Cyclotron Waves, Richard Denton, K. Jordanova, J. Bortnik 2015 Dartmouth College

Resonance Of Relativistic Electrons With Electromagnetic Ion Cyclotron Waves, Richard Denton, K. Jordanova, J. Bortnik

Dartmouth Scholarship

Relativistic electrons have been thought to more easily resonate with electromagnetic ion cyclotron (EMIC) waves if the total density is large. We show that, for a particular EMIC mode, this dependence is weak due to the dependence of the wave frequency and wave vector on the density. A significant increase in relativistic electron minimum resonant energy might occur for the H band EMIC mode only for small density, but no changes in parameters significantly decrease the minimum resonant energy from a nominal value. The minimum resonant energy depends most strongly on the thermal velocity associated with the field line motion …


Laser Vision: Lidar As A Transformative Tool To Advance Critical Zone Science, N. F. Glenn 2015 Boise State University

Laser Vision: Lidar As A Transformative Tool To Advance Critical Zone Science, N. F. Glenn

Geosciences Faculty Publications and Presentations

Observation and quantification of the Earth’s surface is undergoing a revolutionary change due to the increased spatial resolution and extent afforded by light detection and ranging (lidar) technology. As a consequence, lidar-derived information has led to fundamental discoveries within the individual disciplines of geomorphology, hydrology, and ecology. These disciplines form the cornerstones of critical zone (CZ) science, where researchers study how interactions among the geosphere, hydrosphere, and biosphere shape and maintain the “zone of life”, which extends from the top of unweathered bedrock to the top of the vegetation canopy. Fundamental to CZ science is the development of transdisciplinary theories …


Detection Of Small-Scale Rockfall Incidents Using Their Seismic Signature, Achilleas Tripolitsiotis, Antonis Daskalakis, Stelios Mertikas, Dionysios Hristopulos, Zacharias Agioutantis, Panagiotis Partsinevelos 2015 Technical University of Crete, Greece

Detection Of Small-Scale Rockfall Incidents Using Their Seismic Signature, Achilleas Tripolitsiotis, Antonis Daskalakis, Stelios Mertikas, Dionysios Hristopulos, Zacharias Agioutantis, Panagiotis Partsinevelos

Mining Engineering Faculty Publications

Several algorithms have been effectively used to identify the seismic signature of rockfall incidents, which constitute a significant threat for human lives and infrastructure especially when occurring along transportation networks. These algorithms have been mostly evaluated using data from large scale rockfall events that release a large amount of energy. However, low-energy rockfall events (< 100 Joules) triggered by small-sized individual rocks falling from small heights can be severely destructive. In this study, a three-parameter algorithm has been developed to identify low-energy rockfall events. An experimental setup was implemented to 1) validate the results obtained by this algorithm against visual inspection of seismic signals records, 2) define the optimal algorithm parameterization to minimize false alarms, and 3) investigate whether tri-axial vibration monitoring can be replaced by a uniaxial device in order to reduce the installation cost of a real-time rockfall monitoring system. It was found that the success rate of the proposed algorithm exceeds 80% independently of the parameters used, while event identification at a maximum distance with minimal false alarms was achieved when using mean ± 3σ as the threshold criterion and 6 ms and 4 ms as the trigger and event window parameters respectively. Finally, it was found that for the specific experimental setup, a uniaxial device could be used for rockfall event identification.


Field Line Distribution Of Mass Density At Geostationary Orbit, Richard Denton, Kazue Takahashi, Jimyoung Lee, C.K. Zeitler, N.T. Wimer, E. Litscher, H.J. Singer, Kyungguk Min 2015 Dartmouth College

Field Line Distribution Of Mass Density At Geostationary Orbit, Richard Denton, Kazue Takahashi, Jimyoung Lee, C.K. Zeitler, N.T. Wimer, E. Litscher, H.J. Singer, Kyungguk Min

Dartmouth Scholarship

The distribution of mass density along the field lines affects the ratios of toroidal (azimuthally oscillating) Alfv'{e}n frequencies, and given the ratios of these frequencies we can get information about that distribution. Here we assume the commonly used power law form for the field line distribution, rho_{m} = rho_{m,eq} ( L R_{E} /R )^alpha, where rho_{m,eq} is the value of the mass density rho_{m} at the magnetic equator, L is the L shell, R_{E} is the Earth's radius, R is the geocentric distance to a point on the field line, and alpha is the power law coefficient. Positive values of …


Lithologic Properties Of The Upper Ordovician Utica Formation, Michigan Basin, Usa: A Geological Characterization And Assessment Of Carbon Dioxide Confinement Potential, Frank Richard Sattler 2015 Western Michigan University

Lithologic Properties Of The Upper Ordovician Utica Formation, Michigan Basin, Usa: A Geological Characterization And Assessment Of Carbon Dioxide Confinement Potential, Frank Richard Sattler

Masters Theses

The Utica/Maquoketa Shale is considered to be the primary confining layer for Cambro-Ordovician CO2 sequestration targets in the Midwest in the Michigan and Illinois basins, respectively. Prospective regional geologic seals in mudrock formations possess a combination of lithologic properties including nanometer scale pore space, elevated breakthrough pressures for non-wetting fluid phases and ductile mechanical deformation. Mineralogical composition is related to and typically controls these properties.

The objective of this study is to investigate the geological controls on stratigraphic and lithologic variability in the Utica/Collingwood in the Michigan basin. Twelve conventional cores and hundreds of modern well logs from the …


Simulation Of Energetic Particle Precipitation Effects During The 2003-2004 Arctic Winter, C. E. Randall, V. L. Harvey, L. A. Holt, D. R. Marsh, D. Kinnison, B. Funke, P. F. Bernath 2015 Old Dominion University

Simulation Of Energetic Particle Precipitation Effects During The 2003-2004 Arctic Winter, C. E. Randall, V. L. Harvey, L. A. Holt, D. R. Marsh, D. Kinnison, B. Funke, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Energetic particle precipitation (EPP) during the 2003-2004 Arctic winter led to the production and subsequent transport of reactive odd nitrogen (NOx=NO+NO2) from the mesosphere and lower thermosphere (MLT) into the stratosphere. This caused NOx enhancements in the polar upper stratosphere in April 2004 that were unprecedented in the satellite record. Simulations of the 2003-2004 Arctic winter with the Whole Atmosphere Community Climate Model using Specified Dynamics (SD-WACCM) are compared to satellite measurements to assess our understanding of the observed NOx enhancements. The comparisons show that SD-WACCM clearly displays the descent of NOx produced …


Growth In Stratospheric Chlorine From Short-Lived Chemicals Not Controlled By The Montreal Protocol, R. Hossaoni, M. P. Chipperfield, A. Saiz-Lopez, J. J. Harrison, R. von Glasow, R. Sommariva, E. Atlas, M. Navarro, S. A. Montzka, W. Feng, P. F. Bernath 2015 Old Dominion University

Growth In Stratospheric Chlorine From Short-Lived Chemicals Not Controlled By The Montreal Protocol, R. Hossaoni, M. P. Chipperfield, A. Saiz-Lopez, J. J. Harrison, R. Von Glasow, R. Sommariva, E. Atlas, M. Navarro, S. A. Montzka, W. Feng, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We have developed a chemical mechanism describing the tropospheric degradation of chlorine containing very short-lived substances (VSLS). The scheme was included in a global atmospheric model and used to quantify the stratospheric injection of chlorine from anthropogenic VSLS (ClyVSLS) between 2005 and 2013. By constraining the model with surface measurements of chloroform (CHCl3), dichloromethane (CH2Cl2), tetrachloroethene (C2Cl4), trichloroethene (C2HCl3), and 1,2-dichloroethane (CH2ClCH2Cl), we infer a 2013 ClyVSLS mixing ratio of 123 parts per trillion (ppt). Stratospheric injection …


Thermal History Of The Michigan Basin: Results From Thermal Maturation Data And Geodynamic Modelling, Kirk A. Wagenvelt 2015 Western Michigan University

Thermal History Of The Michigan Basin: Results From Thermal Maturation Data And Geodynamic Modelling, Kirk A. Wagenvelt

Masters Theses

Thermal cooling, crustal convection, high temperature fluid advection, and 1.0 Km of eroded overburden are required to explain thermal maturation observations in the Michigan Basin. Observed tectonic subsidence in central Michigan follows an exponential decay indicative of thermal cooling following an anomalous heating event. Crustal convection is responsible for episodes of rapid subsidence coincident with the late Paleozoic Appalachian orogeny. Fluid advection through dilated faults reactivated by the Alleghanian orogeny brought hot fluids (as much as 255⁰ C) to the surface and impacted thermal maturation of organic matter in sediments. Models require 1.0 Km of eroded overburden to model thermal …


Structural Controls On The Distribution Of Groundwater In Southern Sinai, Egypt: Constraints From Geophysical And Remote Sensing Observations, Lamees Mohamed 2015 Western Michigan University

Structural Controls On The Distribution Of Groundwater In Southern Sinai, Egypt: Constraints From Geophysical And Remote Sensing Observations, Lamees Mohamed

Dissertations

An integrated (Very Low Frequency [VLF] electromagnetic, magnetic, remote sensing, field, and Geographic Information System [GIS]) study was conducted over the basement complex in Southern Sinai (Feiran watershed) for a better understanding of the structural controls on the groundwater flow. The increase in satellite-based radar backscattering values following a large precipitation event (date: 17, 18 Jan 2010; amount: 34 mm) was used to identify water-bearing features, here interpreted as preferred pathways for surface water infiltration. Findings include: (1) The distribution of the water bearing features (conductive features) correspond to that of fractures, faults, shear zones, dike swarms, and wadi networks; …


Where Were You When The Mountain Blew? Remembering The Eruption Of Mount St Helens, Brittany Brand 2015 Boise State University

Where Were You When The Mountain Blew? Remembering The Eruption Of Mount St Helens, Brittany Brand

Geosciences Faculty Publications and Presentations

May 18, 1980. On that fateful day, Mt St Helens Volcano in Washington exploded violently after two months of intense earthquake activity and intermittent, relatively weak eruptions, causing the worst volcanic disaster in the recorded history of the United States. – US Geological Survey Special Report

Without checking your calendar, can you remember where you were on at 8:30 am April 24, 2015? Some of you might, but more will likely have to think hard to remember. In contrast, if you ask someone who lived in the Pacific Northwest 35 years ago where they were at 8:32 am on May …


Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui 2015 Chapman University

Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui

Student Scholar Symposium Abstracts and Posters

Being located on the “Ring of Fire” Japan experiences many seismic events. Adding to this, it is located at the convergence of four fault lines where seismic activity will be even more frequent and severe. Although small tremors occurring in an area are indicators of an earthquake to come it only gives minutes of warning. Scientists are now trying to see if latent heat and gas release from fault lines can indicate an earthquake to come with hours or even days of warning. MODIS aqua and terra data will be analyzed in order to see if such precursors can be …


Structure From Motion Elevation Model For Adding Topographic Correction To Ground Penetrating Radar, Leslie A. Mowbray 2015 Portland State University

Structure From Motion Elevation Model For Adding Topographic Correction To Ground Penetrating Radar, Leslie A. Mowbray

Student Research Symposium

High resolution elevation models have become a standard tool in environmental, geological and archaeological investigations, however; the cost of acquiring Lidar in remote areas, on small project sites or over repeated time intervals remains prohibitively expensive. Here, open-source software and GIS are used to create a digital elevation model (DEM) from aerial photos in a process known as Structure from Motion (SfM). This process is a fraction of the cost of Lidar acquisition, and is shown to produce a model with comparable resolution. The photos used here were taken from a camera hung from a balloon flown at Mickey Springs …


Inferring The Oriented Elastic Tensor From Surface Wave Observations: Preliminary Application Across The Western United States, Jiayi Xie, Michael H. Ritzwoller, S. J. Brownlee, B. R. Hacker 2015 University of Colorado Boulder

Inferring The Oriented Elastic Tensor From Surface Wave Observations: Preliminary Application Across The Western United States, Jiayi Xie, Michael H. Ritzwoller, S. J. Brownlee, B. R. Hacker

Environmental Science and Geology Faculty Research Publications

Radial and azimuthal anisotropy in seismic wave speeds have long been observed using surface waves and are believed to be controlled by deformation within the Earth’s crust and uppermost mantle. Although radial and azimuthal anisotropy reflect important aspects of anisotropic media, few studies have tried to interpret them jointly. We describe a method of inversion that interprets simultaneous observations of radial and azimuthal anisotropy under the assumption of a hexagonally symmetric elastic tensor with a tilted symmetry axis defined by dip and strike angles. We show that observations of radial anisotropy and the 2ψ component of azimuthal anisotropy for Rayleigh …


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