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Articles 1351 - 1380 of 2452

Full-Text Articles in Geophysics and Seismology

Use Of An Electrical Impedance Tomography Method To Detect And Track Fractures In A Gelatin Medium, Evan G. Lucas Jan 2014

Use Of An Electrical Impedance Tomography Method To Detect And Track Fractures In A Gelatin Medium, Evan G. Lucas

Dissertations, Master's Theses and Master's Reports - Open

Electrical impedance tomography is applied to the problem of detecting, locating, and tracking fractures in ballistics gelatin. The hardware developed is intended to be physically robust and based on off-the-shelf hardware. Fractures were created in two separate ways: by shooting a .22 caliber bullet into the gelatin and by injecting saline solution into the gelatin. The .22 caliber bullet created an air gap, which was seen as an increase in resistivity. The saline solution created a fluid filled gap, which was seen as a decrease in resistivity. A double linear array was used to take data for each of the …


Time Lapse Seismic Observations And Effects Of Reservoir Compressibility At Teal South Oil Field, Nayyer Islam Jan 2014

Time Lapse Seismic Observations And Effects Of Reservoir Compressibility At Teal South Oil Field, Nayyer Islam

Dissertations, Master's Theses and Master's Reports - Open

One of the original ocean-bottom time-lapse seismic studies was performed at the Teal South oil field in the Gulf of Mexico during the late 1990’s. This work reexamines some aspects of previous work using modern analysis techniques to provide improved quantitative interpretations. Using three-dimensional volume visualization of legacy data and the two phases of post-production time-lapse data, I provide additional insight into the fluid migration pathways and the pressure communication between different reservoirs, separated by faults. This work supports a conclusion from previous studies that production from one reservoir caused regional pressure decline that in turn resulted in liberation of …


Geochemical Studies Of Backfill Aggregates, Lake Sediment Cores And The Hueco Bolson Aquifer, Anita Thapalia Jan 2014

Geochemical Studies Of Backfill Aggregates, Lake Sediment Cores And The Hueco Bolson Aquifer, Anita Thapalia

Open Access Theses & Dissertations

This Dissertation comprises of three different researches that focuses on the application of geochemistry from aggregates, lake sediment cores and Hueco Bolson Aquifer. Each study is independent and presented in the publication format. The first chapter is already published and the second chapter is in revision phase. Overall, three studies measure the large scale (field) as well as bench scale (lab) water-rock interactions influenced by the climatic and anthropogenic factors spans from the field of environmental geology to civil engineering.

The first chapter of this Dissertation addresses the chemical evaluation of coarse aggregates from six different quarries in Texas. The …


Impacting Earthquake Science And Geoscience Education: Educational Programming To Earthquake Relocation, Tina Louise Carrick Jan 2014

Impacting Earthquake Science And Geoscience Education: Educational Programming To Earthquake Relocation, Tina Louise Carrick

Open Access Theses & Dissertations

This Dissertation is comprised of four studies: three related to research on geoscience education and another seismological study of the South Island of New Zealand. The geoscience education research is grounded in 10 years of data collection and its implications for best practices for recruitment and retention of underrepresented minority students into higher education in the geosciences. The seismological component contains results from the relocation of earthquakes from the 2009 Dusky Sound Mw 7.8 event, South Island, New Zealand.

In recent years, many have cited a major concern that U.S. is not producing enough STEM graduates to fit the forecasted …


Geophysical Model Of The Cu-Mo Porphyry Ore Deposit At Copper Flat Mine, Hillsboro, Sierra County, New Mexico, Adrian Emmanuel Gutierrez Jan 2014

Geophysical Model Of The Cu-Mo Porphyry Ore Deposit At Copper Flat Mine, Hillsboro, Sierra County, New Mexico, Adrian Emmanuel Gutierrez

Open Access Theses & Dissertations

A 3D gravity model of the Copper Flat Mine was performed as part of the exploration of new resources in at the mine. The project is located in the Las Animas Mining District in Sierra County, New Mexico. The mine has been producing ore since 1877 and is currently owned by the New Mexico Copper Corporation, which plans o bringing the closed copper mine back into production with innovation and a sustainable approach to mining development. The Project is located on the Eastern side of the Arizona-Sonora-New Mexico porphyry copper Belt of Cretaceous age. Copper Flat is predominantly a Cretaceous …


Mapping Technologically And Economically Important Materials At Lunar And Terrestrial Sites Using Moon Mineralogy Mapper (M3) And Advanced Spaceborne Thermal Emission And Reflection Radiometer (Aster) Data, Douglas L. Standart Jan 2014

Mapping Technologically And Economically Important Materials At Lunar And Terrestrial Sites Using Moon Mineralogy Mapper (M3) And Advanced Spaceborne Thermal Emission And Reflection Radiometer (Aster) Data, Douglas L. Standart

Open Access Theses & Dissertations

This Dissertation comprises three distinct research projects, all of which employ the use of remote sensing and digital image processing methods for the discovery and characterization of mineral resources. Two of the research projects focus on the use of hyperspectral data to identify water and ilmenite on the lunar surface. The third research project involves the use of multispectral data to map alunite in copper porphyry and epithermal silver-gold deposits. Our approach to these problems result in innovative algorithms and geological interpretations that are of use to both planetary science and exploration and the terrestrial mineral industry.

Project I: Towards …


Geophysical Investigation Of Hot Springs In The Vicinity Of Shoshone, California, Felix Dziedzorm Ziwu Jan 2014

Geophysical Investigation Of Hot Springs In The Vicinity Of Shoshone, California, Felix Dziedzorm Ziwu

Open Access Theses & Dissertations

Magnetic and gravity surveys were conducted in the vicinity of Shoshone, California to test a hypothesis from investigating hotsprings within Tecopa and Saratoga which states that deep faults must intersect with a specific orientation relative to the regional stress field in order to create hot springs along the Amargosa River.

Three isolated basalt flows with different gravity and magnetic properties were identified near the Shoshone hot spring. Two of the flows have very low magnetic anomalies and the remaining one has a high magnetic anomaly. The high magnetic anomaly basalt flow also has a significantly higher Bouguer anomaly than the …


Proxy-Based Reconstructions Of Earthquakes And Tsunamis At Quidico, South-Central Chile, Isabel J. Hong Jan 2014

Proxy-Based Reconstructions Of Earthquakes And Tsunamis At Quidico, South-Central Chile, Isabel J. Hong

All Master's Theses

We utilized geomorphic, microfossil, sedimentological, and stratigraphic methods to investigate the paleotsunami history at Quidico, Chile (38.1° S, 73.2° W). A combination of pits, cores, and riverbank exposures provide stratigraphic evidence of 8 sand layers at Quidico, including tsunami deposits from 2010 and 1960. The sands are laterally continuous but display landward thinning, disappearing completely from the stratigraphy 1.2 km inland from the coast. Intervening sediment layers consist of organicrich silts and peat. Grain size analysis shows the sand units are bimodal in distribution whereas the organic-rich silts and peat have a broader, bimodal distribution. Lithological analysis showed similarities among …


Controls On Fault Geometry During Early Stages Of Extension In The Larkspur Hills, Northwest Basin And Range, Diana Jean Strickley Jan 2014

Controls On Fault Geometry During Early Stages Of Extension In The Larkspur Hills, Northwest Basin And Range, Diana Jean Strickley

All Master's Theses

Detailed analyses of normal faults in the Larkspur Hills, CA-NV, northwest Basin and Range, offer insight into factors controlling normal fault initiation, growth, and distribution. N-trending faults in the southern portion of the study area share trends of major range-bounding structures and Pliocene linear volcanic vents; in contrast, NNW- and NNE- trending faults dominate further north and into south-central Oregon. Stress analyses and comparison with experimental and field data suggest that preexisting structures control faults in the northern Larkspur Hills, while faults form perpendicular to σ3 in the southern hills. The change in fault orientations is abrupt, occurring across a …


Doing More With Short Period Data: Determining Magnitudes From Clipped And Over-Run Seismic Data At Mount St. Helens, John J. Wellik Ii Jan 2014

Doing More With Short Period Data: Determining Magnitudes From Clipped And Over-Run Seismic Data At Mount St. Helens, John J. Wellik Ii

Dissertations, Master's Theses and Master's Reports - Open

How can we calculate earthquake magnitudes when the signal is clipped and over-run? When a volcano is very active, the seismic record may saturate (i.e., the full amplitude of the signal is not recorded) or be over-run (i.e., the end of one event is covered by the start of a new event). The duration, and sometimes the amplitude, of an earthquake signal are necessary for determining event magnitudes; thus, it may be impossible to calculate earthquake magnitudes when a volcano is very active. This problem is most likely to occur at volcanoes with limited networks of short period seismometers. This …


Static And Dynamic Stress Change At 27 Volcanoes Of The Central American Volcanic Arc After The Mw. 7.6 Costa Rica Earthquake Of 5 September 2012, Lorenzo Gratton Jan 2014

Static And Dynamic Stress Change At 27 Volcanoes Of The Central American Volcanic Arc After The Mw. 7.6 Costa Rica Earthquake Of 5 September 2012, Lorenzo Gratton

Dissertations, Master's Theses and Master's Reports - Open

Large earthquakes may strongly influence the activity of volcanoes through static and dynamic processes. In this study, we quantify the static and dynamic stress change on 27 volcanoes in Central America, after the Mw 7.6 Costa Rica earthquake of 5 September 2012. Following this event, 8 volcanoes showed signs of activity. We calculated the static stress change due to the earthquake on hypothetical faults under these volcanoes with Coulomb 3.3. For the dynamic stress change, we computed synthetic seismograms to simulate the waveforms at these volcanoes. We then calculated the Peak Dynamic Stress (PDS) from the modeled peak ground …


Tuning, Avo, And Flat-Spot Effects In A Seismic Analysis Of North Sea Block F3, Qiang Guo Jan 2014

Tuning, Avo, And Flat-Spot Effects In A Seismic Analysis Of North Sea Block F3, Qiang Guo

Dissertations, Master's Theses and Master's Reports - Open

Reflection seismic data from the F3 block in the Dutch North Sea exhibits many large-amplitude reflections at shallow horizons, typically categorized as “brightspots ” (Schroot and Schuttenhelm, 2003), mainly because of their bright appearance. In most cases, these bright reflections show a significant “flatness” contrasting with local structural trends.

While flatspots are often easily identified in thick reservoirs, we have often occasionally observed apparent flatspot tuning effects at fluid contacts near reservoir edges and in thin reservoir beds, while only poorly understanding them. We conclude that many of the shallow large-amplitude reflections in block F3 are dominated by flatspots, and …


Did A Submarine Landslide Contribute To The 2011 Tohoku Tsunami?, David R. Tappin, Stephan T. Grilli, Jeffrey C. Harris, Robert J. Geller, Timothy Masterlark, James T. Kirby, Fengyan Shi, Gangfeng Ma, K.K.S. Thingbaijam, P. Martin Mai Jan 2014

Did A Submarine Landslide Contribute To The 2011 Tohoku Tsunami?, David R. Tappin, Stephan T. Grilli, Jeffrey C. Harris, Robert J. Geller, Timothy Masterlark, James T. Kirby, Fengyan Shi, Gangfeng Ma, K.K.S. Thingbaijam, P. Martin Mai

Civil & Environmental Engineering Faculty Publications

Many studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40. m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recorded at three nearshore buoys off Sanriku, nor the timing and dispersion properties of the waveforms at offshore DART buoy #21418. (3) …


Seismic Anisotropy And Mantle Flow Beneath Africa And Arabia, Ahmed Abdalla Elsheikh Jan 2014

Seismic Anisotropy And Mantle Flow Beneath Africa And Arabia, Ahmed Abdalla Elsheikh

Doctoral Dissertations

"In spite of numerous studies, the mechanisms for the rifting, uplifting, and volcanism on the African plate remain enigmatic. The most popular hypotheses proposed for explaining these tectonic phenomena involve edge-driven small-scale mantle convection and the thermal or dynamic effects of one or more mantle plumes. In this study we use continental scale shear-wave splitting (SWS) measurements to provide additional constraints on the various models of rifting, uplifting, and volcanism of the Cameroon Volcanic Line (CVL) and the Arabian plate. The splitting of P-to-S converted phases at the core-mantle boundary on the receiver side (XKS including PKS, SKKS, and SKS) …


Biomineralization Of Carbonates In Modern Microbial Sediments And Its Implications For Co₂ Sequestration, Varun Gnanaprian Paul Jan 2014

Biomineralization Of Carbonates In Modern Microbial Sediments And Its Implications For Co₂ Sequestration, Varun Gnanaprian Paul

Doctoral Dissertations

"Several bacterial species influence carbonate mineral precipitation by modifying pH, alkalinity, Ca²⁺ activity and by providing nucleation sites for mineralization. Two studies have been undertaken to explore microbial influence in the mineralization of carbonates. In the first study, the ability of sulfate-reducing bacteria (SRB) to induce carbonate mineralization was investigated as a means to enhance mineral sequestration of CO₂. Sulfate-reducing bacteria enriched from hypersaline Storr's Lake, The Bahamas; Lake Estancia, New Mexico; and Great Salt Plains Lake, Oklahoma, were tested in reactors under varying CO₂ concentrations. Carbonate mineral precipitation was achieved only in reactors with Lake Estancia SRB community and …


Study Of Filled Dolines By Using 3d Stereo Image Processing And Electrical Resistivity Imaging, Mateja Breg Valjavec Jan 2014

Study Of Filled Dolines By Using 3d Stereo Image Processing And Electrical Resistivity Imaging, Mateja Breg Valjavec

International Journal of Speleology

This article deals with doline degradation due to uncontrolled waste dumping in the past in the Logatec Polje in Slovenia. It introduces a concept for determining 3D geometric characteristics (shape, depth, radius, area, and volume) of formerly concave landforms (i.e., recently filled dolines) by using a combination of two methods: (1) photogrammetric stereo processing of archival aerial photographs and (2) electrical resistivity imaging (ERI). To represent, visualize, and study the characteristics of the former surface morphology (i.e., the dolines before they were filled), a digital terrain model (DTM) for 1972 (DTM1972) was made using digital photogrammetry processing of five sequential …


Attribute Analyses Of Gpr Data For Detecting And Identifying Heavy Minerals, Aycan Catakli Dec 2013

Attribute Analyses Of Gpr Data For Detecting And Identifying Heavy Minerals, Aycan Catakli

Theses and Dissertations

Attribute analyses have been used successfully in seismic applications for many years. In this study, the application of the attribute analyses to Ground Penetrating Radar (GPR) data has been proposed to detect and identify heavy minerals within the Moon soil (regolith). Lunar samples are mostly composed of heavy minerals such as ilmenite, plagioclase, olivine and pyroxene, a characteristic that makes lunar soil a source for elements such as titanium, oxygen and iron. The main goal of this study is to demonstrate the use of GPR method for detecting and mapping heavy minerals concentrations. The attribute analyses used in this study …


Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas Dec 2013

Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas

Natural Resources Management and Environmental Sciences

The city of Los Osos sits on top of a coastal groundwater aquifer which is the sole supplier of all its residential, agricultural, and industrial water needs. Lacking a sewer system, the upper aquifer became progressively contaminated with nitrates over several decades. Groundwater pumping eventually shifted to the lower aquifer, however seawater intrusion of the lower aquifer caused by over-pumping has further degraded water quality. The Los Osos groundwater basin provides an excellent field region to examine the utility of geophysical methods for characterizing aquifer structure. In this study shallow (<20 >m) electrical resistivity imaging methods were performed at two …


Lithostratigraphic And Petrophysical Analysis Of The Middle Devonian Marcellus Shale At The Mamont Prospect, Westmoreland County, Pennsylvania, Ty Taylor Dec 2013

Lithostratigraphic And Petrophysical Analysis Of The Middle Devonian Marcellus Shale At The Mamont Prospect, Westmoreland County, Pennsylvania, Ty Taylor

All Theses

The organic-rich Middle Devonian Marcellus Shale of the Appalachian basin is a rapidly developing natural gas play. Stratigraphic boundaries of the Marcellus Shale in Westmoreland County, Pennsylvania were identified using geophysical logs from 10 vertical gas-producing wells in a 23 sq. km area. Gamma-ray, bulk density, and resistivity well logs were examined to assess hydrocarbon potential. Values of porosity, total organic carbon (TOC), and water saturation (SW) were derived and mapped by incorporating well-log data into Marcellus-specific formulas. Gamma-ray, penetration (minutes per foot drilled), and mud-logging gas (total gas) from 12 horizontal wells from within the study area were also …


Teaching Geophysics With A Vertical-Component Seismometer, Kasper Van Wijk, Ted Channel, Karen Viskupic, Martin L. Smith Dec 2013

Teaching Geophysics With A Vertical-Component Seismometer, Kasper Van Wijk, Ted Channel, Karen Viskupic, Martin L. Smith

Geosciences Faculty Publications and Presentations

Earthquakes are some of the more dramatic expressions of the dynamics of our planet. The sudden release of stress built up slowly by tectonic or volcanic processes often has far-reaching consequences, and can be measured (in classrooms) around the world. This is one reason why designing and building seismometers has been a popular activity,1,2 and why different versions of “Seismometer in Schools” projects thrive in the United States, Australia, and Europe. We present a cheap, robust, and easy-to-build seismometer—called the TC1 —to measure seismic displacements in the vertical direction. Its components are easy to obtain and assemble, yet the …


Consolidation And Suspension Of Mud From Lake Lery And Relevance To Wetland Restoration In Louisiana, Edward L. Lo Dec 2013

Consolidation And Suspension Of Mud From Lake Lery And Relevance To Wetland Restoration In Louisiana, Edward L. Lo

Honors Capstones

No abstract provided.


Geophysical Investigations Of The Seattle Fault Zone In Western Washington And A Geothermal System At Mount Princeton, Colorado, Andrew Patrick Lamb Dec 2013

Geophysical Investigations Of The Seattle Fault Zone In Western Washington And A Geothermal System At Mount Princeton, Colorado, Andrew Patrick Lamb

Boise State University Theses and Dissertations

We use an array of existing and modified geophysical techniques to investigate the active Seattle thrust fault zone in western Washington and a geothermal system at Mt. Princeton Colorado. Through the integration of different geophysical methods, we can extend our observations of the surface geology to beneath the subsurface, thereby giving us a greater understanding of the structures and their kinematic interplay.

We find geophysical evidence through the use of potential field and seismic data for the Seattle fault zone extending further to the west than previously thought. We also find evidence that the Seattle fault zone may be linked …


Integrated Geophysical Exploration Of A Known Geothermal Resource: Neal Hot Springs, Clinton Ryan Colwell Dec 2013

Integrated Geophysical Exploration Of A Known Geothermal Resource: Neal Hot Springs, Clinton Ryan Colwell

Boise State University Theses and Dissertations

I present an integrated geophysical characterization of the Neal Hot Springs geothermal system in eastern Oregon. This newly established 23 MW geothermal production site is located in a region of complex geology and intersecting faults associated with two major extensional systems; the Oregon-Idaho Graben and the western Snake River Plain. The intersection of two dominant fault orientations, coupled with a high geothermal gradient from relatively thin continental crust and radioactive decay from a shallow granitic body, produces the pathways and heat needed for deep water circulation at Neal Hot Springs. New geologic mapping, geochemistry, and measurements from several boreholes in …


Glacier Slip And Seismicity Induced By Surface Melt, Peter L. Moore, J. Paul Winberry, Neal R. Iverson, Knut A. Christianson, Sridhar Anandakrishnan, Miriam Jackson, Mark E. Mathison, Denis Cohen Dec 2013

Glacier Slip And Seismicity Induced By Surface Melt, Peter L. Moore, J. Paul Winberry, Neal R. Iverson, Knut A. Christianson, Sridhar Anandakrishnan, Miriam Jackson, Mark E. Mathison, Denis Cohen

All Faculty Scholarship for the College of the Sciences

Many of the key processes governing fast glacier flow involve interaction between a glacier and its basal hydrological system, which is hidden from direct observation. Passive seismic monitoring has shown promise as a tool for remotely monitoring basal processes, but lack of glacier-bed access prevents clear understanding of the relationships between subglacial processes and corresponding seismic emissions. Here we describe direct measurements of basal hydrology, sliding, and broadband seismicity made in a unique subglacial facility in Norway during the onset of two summer melt seasons. In the most pronounced of these episodes, rapid delivery of surface meltwater to the bed …


Hydraulic Conductivity Imaging From 3-D Transient Hydraulic Tomography At Several Pumping/Observation Densities, Michael Cardiff, Warren Barrash, Peter K. Kitanidis Nov 2013

Hydraulic Conductivity Imaging From 3-D Transient Hydraulic Tomography At Several Pumping/Observation Densities, Michael Cardiff, Warren Barrash, Peter K. Kitanidis

CGISS Publications and Presentations

3-D Hydraulic tomography (3-D HT) is a method for aquifer characterization whereby the 3-D spatial distribution of aquifer flow parameters (primarily hydraulic conductivity, K) is estimated by joint inversion of head change data from multiple partially penetrating pumping tests. While performance of 3-D HT has been studied extensively in numerical experiments, few field studies have demonstrated the real-world performance of 3-D HT. Here we report on a 3-D transient hydraulic tomography (3-D THT) field experiment at the Boise Hydrogeophysical Research Site which is different from prior approaches in that it represents a “baseline” analysis of 3-D THT performance using …


A Detailed Seabed Signature From Hurricane Sandy Revealed In Bedforms And Scour, Arthur Trembanis, Carter Duval, Jonathan Beaudoin, Val E. Schmidt, Doug Miller, Larry A. Mayer Oct 2013

A Detailed Seabed Signature From Hurricane Sandy Revealed In Bedforms And Scour, Arthur Trembanis, Carter Duval, Jonathan Beaudoin, Val E. Schmidt, Doug Miller, Larry A. Mayer

Center for Coastal and Ocean Mapping

On 30 October 2012, Hurricane Sandy made landfall near Brigantine New Jersey bringing widespread erosion and damage to the coastline. We have obtained a unique set of high-resolution before and after storm measurements of seabed morphology and in situhydrodynamic conditions (waves and currents) capturing the impact of the storm at an inner continental shelf field site known as the “Redbird reef”. Understanding the signature of this storm event is important for identifying the impacts of such events and for understanding the role that such events have in the transport of sediment and marine debris on the inner continental shelf. …


Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2013

Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Single And Multi-Date Landsat Classifications Of Basalt To Support Soil Survey Efforts, Jessica J. Mitchell, Rupesh Shrestha, Carol A. Moore-Ellison, Nancy F. Glenn Oct 2013

Single And Multi-Date Landsat Classifications Of Basalt To Support Soil Survey Efforts, Jessica J. Mitchell, Rupesh Shrestha, Carol A. Moore-Ellison, Nancy F. Glenn

Geosciences Faculty Publications and Presentations

Basalt outcrops are significant features in the Western United States and consistently present challenges to Natural Resources Conservation Service (NRCS) soil mapping efforts. Current soil survey methods to estimate basalt outcrops involve field transects and are impractical for mapping regionally extensive areas. The purpose of this research was to investigate remote sensing methods to effectively determine the presence of basalt rock outcrops. Five Landsat 5 TM scenes (path 39, row 29) over the year 2007 growing season were processed and analyzed to detect and quantify basalt outcrops across the Clark Area Soil Survey, ID, USA (4,570 km2). The …


Characterization Of Fractures Subjected To Normal And Shear Stress, Min-Kwang Choi Oct 2013

Characterization Of Fractures Subjected To Normal And Shear Stress, Min-Kwang Choi

Open Access Dissertations

Results from a series of laboratory experiments to determine fracture specific stiffness, for a fracture subjected to shear and normal stress, are presented and analyzed. The experimental work focuses on the determination of relations between normal and shear fracture specific stiffness and between spatial distribution of fracture specific stiffness and fluid flow through the fracture

The ratio of shear to normal fracture specific stiffness is experimentally investigated on a fracture subjected to shear as well as normal stress. Synthetic fractures made of gypsum and lucite were prepared with different fracture surface conditions: either well-mated or non-mated. For well-mated fracture surfaces, …


Megathrust Splay Faults At The Focus Of The Prince William Sound Asperity, Alaska, Lee M. Liberty, Shaun P. Finn, Peter J. Haeussler, Thomas L. Pratt, Andrew Peterson Oct 2013

Megathrust Splay Faults At The Focus Of The Prince William Sound Asperity, Alaska, Lee M. Liberty, Shaun P. Finn, Peter J. Haeussler, Thomas L. Pratt, Andrew Peterson

CGISS Publications and Presentations

[1] High-resolution sparker and crustal-scale air gun seismic reflection data, coupled with repeat bathymetric surveys, document a region of repeated coseismic uplift on the portion of the Alaska subduction zone that ruptured in 1964. This area defines the western limit of Prince William Sound. Differencing of vintage and modern bathymetric surveys shows that the region of greatest uplift related to the 1964 Great Alaska earthquake was focused along a series of subparallel faults beneath Prince William Sound and the adjacent Gulf of Alaska shelf. Bathymetric differencing indicates that 12 m of coseismic uplift occurred along two faults that reached the …