Estimating The Rayleigh-Wave Impulse Response Between Seismic Stations With The Cross Terms Of The Green Tensor,
2011
Boise State University
Estimating The Rayleigh-Wave Impulse Response Between Seismic Stations With The Cross Terms Of The Green Tensor, Kasper Van Wijk, T. Dylan Mikesell, Vera Schulte-Pelkum, Josh Stachnik
CGISS Publications and Presentations
The development of ambient noise tomography has provided a powerful tool to investigate the Earth's subsurface with increased resolution. Most commonly, surface-wave tomography is performed on inter-station estimates of the vertical component of Rayleigh waves, stemming from crosscorrelations of ocean-generated noise. Here, we estimate the cross terms of the Rayleigh-wave Green tensor, and show this is less sensitive to signal not in-line with the seismic stations. We illustrate this result with the Batholiths temporary seismic deployment, showing estimates of the Rayleigh wave with a higher signal-to-noise ratio and a consequently better phase-velocity dispersion curve. This approach provides an opportunity for …
Predicted Velocity And Density Structure Of The Exhuming Papua New Guinea Ultrahigh‐Pressure Terrane,
2011
University of California - Santa Barbara
Predicted Velocity And Density Structure Of The Exhuming Papua New Guinea Ultrahigh‐Pressure Terrane, Sarah J. Brownlee, Bradley R. Hacker, Matthew Salisbury, Gareth Seward, Timothy A. Little, Suzanne A. Baldwin, Geoffrey A. Abers
Environmental Science and Geology Faculty Research Publications
New electron backscatter diffraction measurements show that the Papua New Guinea (PNG) ultrahigh‐pressure (UHP) terrane is dominated by rocks with weakly oriented quartz and feldspar and less abundant strongly oriented hornblende, clinopyroxene, and mica. Velocities measured at high pressures (600 MPa) show that VP is 5.8–6.3 km/s for gneiss samples, 6.5–7.7 km/s for amphibolite, and 7.7–8.2 km/s for eclogite and VS is 3.4–3.9 km/s for gneiss, 4.0–4.4 km/s for amphibolite, and 4.5–4.6 km/s for eclogite. Velocities and anisotropies calculated from mineral crystal preferred orientations (CPOs) are equivalent to within 5% of the measured values. The highest seismic anisotropy …
Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks,
2011
California Polytechnic State University - San Luis Obispo
Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks, Aaron M. Jahoda, Friedemann T. Freund
STAR Program Research Presentations
Much of the devastation and damage of earthquakes can be attributed to the fact that they occur suddenly and without much warning, which limits the ability of people to evacuate and/or properly prepare. One method, however, that might be used to predict seismic events is the generation of electric currents in rocks when stresses are applied. It is observed in this research that the application of direct force onto samples of igneous rock causes the rocks to generate a measurable current, which is attributed to positive-hole charges moving within the oxygen sub-lattice. Because large and changing forces are acted upon …
Penrose Conference Report: Neotectonics Of Arc-Continent Collision,
2011
University of Texas at Austin
Penrose Conference Report: Neotectonics Of Arc-Continent Collision, Paul Mann, Carlos Vargas, Caroline Whitehill
Geological Sciences Faculty Scholarship
Collisions of arcs with continents are some of the most significant tectonic processes on Earth, leading to crustal accretion, continental growth, formation of sedimentary basins, large areas of regional uplift and deformation, complex interactions between continuous and torn subducted slabs and the surrounding mantle, and large regions of large earthquakes and seismic, volcanic, and landslide hazards that can threaten the lives of millions.
The objective of this conference was to bring together an international group of scientists to discuss the neotectonics and seismic hazards of shallow slab subduction in areas of arc-continent collisions.
Establishing Confidence In Surface Wave Determined Soil Profiles,
2011
Boise State University
Establishing Confidence In Surface Wave Determined Soil Profiles, Paul Michaels
CGISS Publications and Presentations
Surface waves can be used to determine the shear velocity profile from the ground surface to some depth limited by the spectral band of the seismic source. A number of factors influence the uncertainties of the determined profile. The field acquisition factors include the deployment geometry of geophones, the spectral characteristics of the geophones, recording instruments, and seismic source. A key data processing factor is the determination of a dispersion curve from the field recordings. Finally, there are important choices in conducting the inversion of the dispersion curve which leads to the final soil profile. Even if the field factors …
Full Conference Program With Abstracts,
2011
Western Kentucky University Hoffman Institute
Full Conference Program With Abstracts, Jason S. Polk, Leslie A. North
International 2011 Conference on Karst Hydrogeology and Ecosystems
No abstract provided.
Groundwater Research In Middle Earth,
2011
California Polytechnic State University - San Luis Obispo
Groundwater Research In Middle Earth, Thomas Lapoint
Liberal Arts and Engineering Studies
My senior project focused on studying saltwater intrusion in a coastal town of New Zealand. I feel lucky that I was able to travel to such a distant place, conduct research that was insightful and interesting, and immerse myself in an international culture all in the name of my education. As a Liberal Arts and Engineering Studies student, I aim to analyze not only the cultural differences and similarities that the foreign environment offers to me but also the detailed, technical, engineering aspect of my research. I believe that my education should be approached with a well rounded perspective that …
Effect Of Attenuation Relationships On Seismic Site Response Analysis,
2011
Morehead State University
Effect Of Attenuation Relationships On Seismic Site Response Analysis, Maryam Motamed
Morehead State Theses and Dissertations
Presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirement for the Degree of Master of Science by Maryam Motamed on May 12, 2011.
Interpretation Of Rayleigh-Wave Ellipticity Observed With Multicomponent Passive Seismic Interferometry At Hekla Volcano, Iceland,
2011
Boise State University
Interpretation Of Rayleigh-Wave Ellipticity Observed With Multicomponent Passive Seismic Interferometry At Hekla Volcano, Iceland, Matthew M. Haney, Andrew Nies, Tim Masterlark, Sarah Needy, Rikke Pedersen
CGISS Publications and Presentations
The 2010 eruption of Eyjafjallajökull has drawn increased attention to Iceland’s Eastern Volcanic Zone (EVZ) due to the threat it poses to the heavily used air-traffic corridors of the northern Atlantic Ocean. Within the EVZ, Hekla is historically one of the most active volcanoes and has exhibited a decadal eruption pattern for the past 40 years. Hekla most recently erupted in 2000 and is thus ripe for another decadal eruption. Because Hekla is generally aseismic, except for a brief time period (hours) leading up to an eruption, monitoring has previously depended on precursory deformation signals (Linde et al., 1993). As …
Complex Vs Profiles To 100 M Depth From Rayleigh Waves And 3-D Vs Model For Las Vegas Valley,
2011
University of Nevada, Las Vegas
Complex Vs Profiles To 100 M Depth From Rayleigh Waves And 3-D Vs Model For Las Vegas Valley, Helena Murvosh
UNLV Theses, Dissertations, Professional Papers, and Capstones
A three-dimensional (3-D) shear wave velocity (VS) model was developed for the heterogeneous shallow sediments (to nearly 400 m) of the Las Vegas Valley (LVV), Nevada. The model was based on more than 200 VS profiles and 1400 geologic well logs. Five sediment units including a cemented unit were defined from geologic log descriptions. A characteristic VS profile for four of the units was obtained by correlating between closely spaced pairs of VS and sediment data; a constant VS was assigned to the cemented unit. VS profiles were then assigned to each well location based on type of sediment according …
Elastic Plastic Self Consistent (Epsc) Modeling Of Plastic Deformation In Fayalite Olivine,
2011
University of Nevada, Las Vegas
Elastic Plastic Self Consistent (Epsc) Modeling Of Plastic Deformation In Fayalite Olivine, Christopher J. Cline Ii, Pamela Burnley
Festival of Communities: UG Symposium (Posters)
We are using an Elastic Plastic Self Consistent Model (a type of numerical simulation) to study deformation of olivine. Olivine is one of the major constituents of the Earth’s upper mantle and its deformation properties have an important influence on how the Earth’s crust deforms. For example, the flow strength of olivine limits the size of the largest earthquakes and the heights of the tallest mountains on Earth. By comparing the results of our simulations with data from olivine deformation experiments we are able to better interpret the experimental data.
In-Situ Synchrotron X-Ray Diffraction Study Of Quartz Deformation Using The D-Dia Apparatus,
2011
University of Nevada, Las Vegas
In-Situ Synchrotron X-Ray Diffraction Study Of Quartz Deformation Using The D-Dia Apparatus, May Sas, Dawn Pape, Brian Erickson, Sylvia-Monique Thomas, Pamela Burnley
Festival of Communities: UG Symposium (Posters)
Deformation is a rock’s mechanical response to external parameters such as temperature and pressure. Knowledge of deformation is necessary to understand geodynamic processes. The behavior of rocks and minerals during deformation depends on the behavior of individual grains within those minerals as they interact. The mineral we are studying is quartz, which we chose since it is very well studied and is highly abundant. We use high-pressure high temperature experiments to simulate conditions of Earth’s interior and the D-DIA apparatus combined with synchrotron x-ray diffraction allows us to record data directly during the process of deformation. The data we collect …
Relation Of Recent Seismicity (1988-Present) To The 1958 Huslia, Alaska Earthquake Sequence,
2011
Department of Geological Sciences, University of Texas at ElPaso
Relation Of Recent Seismicity (1988-Present) To The 1958 Huslia, Alaska Earthquake Sequence, Abigail Monreal^, Diane I. Doser*
COURI Symposium Abstracts, Spring 2011
We have examined how recent seismicity in the Huslia region of central Alaska is related to active faults and the 1958 earthquake sequence (with at least 3 events of magnitude >6). Most of this region is swampy lowland dominated by alluvial material deposited by the Koyukuk River, making surficial identification of active faults difficult. This portion of Alaska is also of interest because it appears to be a region in transition between the strike-slip faulting of the Salcha-Fairbanks-Minto Flats seismic zone and normal faulting of western Alaska (Norton Sound/Seward Peninsula). Researchers have suggested this change in the nature of faulting …
Mapping Unmarked Graves In The Mescalero Apache Indian Reservation,
2011
Department of Geological Sciences, University of Texas at El Paso
Mapping Unmarked Graves In The Mescalero Apache Indian Reservation, Ashley Galusina Nauer^, Stephanie Chavez^, Laura Serpa*
COURI Symposium Abstracts, Spring 2011
Citizens living on the Apache Indian Reservation in Mescalero, New Mexico have experienced difficulty in burying their dead because when they dig a new grave, they often find a body from an earlier burial. The reservation does not have rigorous rules on locating and marking graves and, thus, there are numerous unmarked burial sites within and outside of the existing cemeteries. Officials from the reservation approached the Geological Sciences Department for assistance to map grave locations in the area’s three graveyards. In this project, we will use shallow ground-penetrating radar (GPR) to find the graves and digital global positioning system …
Studies Of Seismicity Near The Active Volcano Mt. Spurr,
2011
Department of Geological Sciences, University of Texas at El Paso
Studies Of Seismicity Near The Active Volcano Mt. Spurr, Sarah J. Olivas^, Diane I. Doser*
COURI Symposium Abstracts, Spring 2011
Seismicity patterns and fault orientations can indicate local stress fields related to volcanic eruptions. There have been many moderate magnitude, shallow earthquakes occurring in the Strandline Lake region about 100km from Anchorage, Alaska near the active volcano, Mt. Spurr. Previous researchers have found that the local stress under Mt. Spurr, before and after its 1992 eruption (1992-1997), differed from the regional stresses, which are related to subduction of the Pacific Plate and Yakutat micro plate. We are analyzing location and patterns of earthquakes occurring since 1998 to determine if more recent seismicity is similar to that occurring before or after …
Using Gravitational And Magnetic Data To Understand Interactions Between Active Seismic Zones Within The Interior Of Alaska,
2011
Department of Geological Sciences, University of Texas at El Paso
Using Gravitational And Magnetic Data To Understand Interactions Between Active Seismic Zones Within The Interior Of Alaska, Shane M. Schinagel^, Diane I. Doser*
COURI Symposium Abstracts, Spring 2011
Differences in rock density, along with changes in the orientation of the magnetic field, provide vital information about the tectonic environment within the interior of Alaska in a region where outcrop exposure is poor due to recent glacial and fluvial activity. Analysis of the gravity and magnetic field can help identify relationships between recent (1989-2008) and historic (pre-1971) seismicity and suspected strike-slip, reverse, and thrust faults within the region, as differences in density and magnetic properties of materials may be observed across fault zones. Our overall objective is to better understand the complicated interactions between the strike-slip Denali fault system …
Seismic Study Of Carlsbad, Nm,
2011
University of Texas at El Paso
Seismic Study Of Carlsbad, Nm, Steven M. Espinosa^, Aaron A. Velasco*
COURI Symposium Abstracts, Spring 2011
Since January 1, 2000, there have been numerous earthquakes recorded in the vicinity of Carlsbad, NM. Importantly, these shallow (10km) earthquakes with magnitudes < 4.3, do not have a fault or system of faults directly mapped to explain these events. We will be relocating the largest and most recent earthquake, which occurred 25km west of Carlsbad, NM of magnitude 4.1 on March 28, 2010. Data recorded by seismic stations from the USArray, a large National Science Foundation project, and our local Kidd Observatory will be used for this analysis. The use of Standing Order of Data (SOD) allows us access seismograms, and the Seismic Analysis Code (SAC) helps in the analysis of the seismic data. We will correlate the hypocenters of aftershocks to the main event hypocenter, allowing us to identify the fault plane. Once a fault plane has been identified, we will begin work on relocating a second event, thereby identifying the responsible faults. We believe that faulting in this area is related to the Rio Grande Rift extension and can be used as evidence for an active rift.
Possible Connections Between A Great Earthquake And An Earthquake Sequence: Samoa Islands (8.1) And Vanuatu Islands,
2011
University of Texas at El Paso
Possible Connections Between A Great Earthquake And An Earthquake Sequence: Samoa Islands (8.1) And Vanuatu Islands, Marissa Cameron^, Aaron A. Velasco*
COURI Symposium Abstracts, Spring 2011
Dynamic triggering describes the possibility that certain earthquakes cause, or ‘trigger’ new earthquakes at great distances. Static triggering is common and is known to cause aftershocks very near to the site, generally within two lengths of the ruptured fault. Dynamically triggered events can occur at distances beyond two fault lengths, however the mechanism for how this can occur remains unknown. By examining seismic data collected from possible dynamically triggered events, we may gain a better understanding of the mechanisms at work. On September 29, 2009, an earthquake of magnitude 8.1 took place along a 175 km fault rupture in Samoa, …
Sensitivity Analysis Of Empirical Parameters In The Ionosphere-Plasmasphere Model,
2011
Air Force Institute of Technology
Sensitivity Analysis Of Empirical Parameters In The Ionosphere-Plasmasphere Model, Janelle V. Jenniges
Theses and Dissertations
A sensitivity analysis of empirical parameters used in physics-based models was completed in this study to determine their effect on electron densities and total electron content (TEC) in the ionosphere. The model used was the Ionosphere-Plasmasphere Model (IPM) developed by Utah State University. The empirical parameters studied include the O+/O collision frequency, zonal wind, secondary electron production, nighttime ExB drifts, and tidal structure. The sensitivity analysis was completed by comparing a default run of the IPM to a run with the parameter adjusted for three geophysical cases. Many of the comparisons resulted in nonlinear changes to the model …
Taxonomy, Nomenclature, And Evolution Of The Early Schubertellid Fusulinids,
2011
Boise State University
Taxonomy, Nomenclature, And Evolution Of The Early Schubertellid Fusulinids, Vladimir I. Davydov
Geosciences Faculty Publications and Presentations
The types of the species belonging to the fusulinid genera Schubertella and Eoschubertella were examined from publications and type collections. Eoschubertella in general possesses all the features of Schubertella and therefore is a junior synonym of the latter. However, the concept of Eoschubertella best describes the genus Schubertina with its type species Schubertina curculi. Schubertina is closely related to the newly established genus Grovesella the concept of which is emended in this paper. Besides Schubertella, Schubertina, and Grovesella, the genera Mesoschubertella, Biwaella are reviewed and three new species, Grovesella nevadensis, Biwaella zhikalyaki, and Biwaella poletaevi, are described. The phylogenetic relationships …
