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Earth Sciences

Earthquakes

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Articles 31 - 60 of 97

Full-Text Articles in Physical Sciences and Mathematics

Ages Of Prehistoric Earthquakes On The Banning Strand Of The San Andreas Fault, Near North Palm Springs, California, Bryan Castillo Jun 2019

Ages Of Prehistoric Earthquakes On The Banning Strand Of The San Andreas Fault, Near North Palm Springs, California, Bryan Castillo

Electronic Theses, Projects, and Dissertations

We studied a paleoseismic trench that was excavated across the Banning strand of the San Andreas Fault by Petra Geosciences (33.9172°, -116.538°). The trench exposed a ~40 m wide fault zone in interbedded alluvial sand gravel, silt and clay deposits. We present the first paleoseismic record for the Banning strand of the southern San Andreas Fault. The most recent event occurred sometime between 730 and 950 cal BP, potentially coincident with rupture of the San Gorgonio Pass thrust. We interpret that five earthquakes have occurred since 3.3-2.5 ka and eight earthquakes have likely occurred since 7.1-5.7 ka. It is possible …


Micro- To Macro-Scale Structural And Lithological Architecture Of Basal Nonconformities: Implications For Fluid Flow And Injection Induced Seismicity, Garth Hesseltine May 2019

Micro- To Macro-Scale Structural And Lithological Architecture Of Basal Nonconformities: Implications For Fluid Flow And Injection Induced Seismicity, Garth Hesseltine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rising incidents of earthquakes caused by human activity in the United States, known as induced earthquakes, is a growing concern. Induced earthquakes may occur when fluid and/or wastewater is injected several kilometers beneath the Earth’s surface into sedimentary rocks. Fluids and pressures can migrate from the sedimentary rocks, which are typically friendlier to fluid flow, into underlying less friendlier crystalline rocks along fluid pathways weakening and possibly reactivating preexisting faults. Understanding potential fluid pathways and/or barriers from the sedimentary rocks to crystalline rocks is crucial. I investigate the structure, composition, and heterogeneity of rocks near the contact between the sedimentary …


Dynamic Triggering Of Earthquakes Within The State Of Utah, Usa, David Lewis Guenaga Jan 2019

Dynamic Triggering Of Earthquakes Within The State Of Utah, Usa, David Lewis Guenaga

Open Access Theses & Dissertations

Understanding the stress state of faults and the stress needed to trigger earthquakes remains a fundamental goal for understanding the earthquake cycle. We focus on deciphering the stress of faults by studying seismic waves from large, distant earthquakes that trigger local seismicity, called remote or dynamic triggering. Utilizing 17 years of waveform and catalog data (2000-2017) from seismic regional networks (i.e., EarthScope USArray Transportable Array, United States Geological Survey, and University of Utah Regional networks), we search for triggered seismicity in the state of Utah following 227 large magnitude (M ≥ 7) distant earthquakes. Utah provides a long-standing regional network …


An Update Of Seismic Monitoring And Research In The Vicinity Of The Paducah Gaseous Diffusion Plant: January 2013–December 2017, Zhenming Wang, Edward W. Woolery, N. Seth Carpenter Jan 2019

An Update Of Seismic Monitoring And Research In The Vicinity Of The Paducah Gaseous Diffusion Plant: January 2013–December 2017, Zhenming Wang, Edward W. Woolery, N. Seth Carpenter

Report of Investigations--KGS

From January 2013 to December 2017, the Kentucky Geological Survey monitored earthquakes and conducted research on seismic hazards in the vicinity of the Paducah Gaseous Diffusion Plant, a former uranium enrichment facility, in western Kentucky. Fifteen earthquakes with magnitude greater than 3.0 occurred in the area during this period, and data were collected from the Central U.S. Seismic Observatory and the vertical seismic array at the gaseous diffusion plant. This monitoring improved our understanding of seismic-wave propagation through thick sediments and ground-motion site effects, as well as fault locations in the New Madrid Seismic Zone, ground-motion attenuation, and seismic-hazard assessment. …


Possible Hydroseismic Triggering For Small Earthquakes Occurring Within The Fox River Valley, Northeastern Illinois, James Benco Jan 2019

Possible Hydroseismic Triggering For Small Earthquakes Occurring Within The Fox River Valley, Northeastern Illinois, James Benco

Graduate Research Theses & Dissertations

In February, 2010 the town of Lily Lake experienced a magnitude 3.8 earthquake. This was followed by small earthquakes of magnitude 2-3 in the same general area in 2012 (McHenry), 2013 (Campton Hills) and 2015 (Lake of the Hills). Seismicity within this region is poorly understood. The Fox River Valley (here defined as the Fox River drainage basin) area is not historically seismically active, nor does it lie above a mapped fault. This study examines the timing of these earthquakes and the hypothesis they were triggered by pore-pressure increases at depth from large rainfall events several months earlier. A pressure …


Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz Jan 2019

Exploring Dynamic Triggering Of Earthquakes Within The United States & Quaternary Faulting And Urban Seismic Hazards In The El Paso Metropolitan Area, Richard Alexander Alfaro-Diaz

Open Access Theses & Dissertations

Technological advances in combination with the onslaught of data availability allow for large seismic data streams to automatically and systematically be recorded, processed, and stored. Here, we develop an automated approach to identify small, local earthquakes within these large continuous seismic data records. Our aim is to automate the process of detecting small seismic events triggered by a distant large earthquake, recorded at a single station. Specifically, we apply time-domain short-term average (STA) to long-term average (LTA) ratio algorithms to three-component data to create a catalog of detections. We remove some of the false detections by requiring the detection be …


Discovery Of Paleotsunami Deposits Along Eastern Sunda Arc: Potential For Megathrust Earthquakes In Bali, Hanif Ibadurrahman Sulaeman Dec 2018

Discovery Of Paleotsunami Deposits Along Eastern Sunda Arc: Potential For Megathrust Earthquakes In Bali, Hanif Ibadurrahman Sulaeman

Theses and Dissertations

Several laterally extensive candidate tsunami deposits are preserved along coastlines facing the eastern Java Trench, indicating it has experienced mega-thrust earthquakes in the past. We investigated 37 coastal sites in Bali, Lombok, Sumba and Timor islands, many of which preserve course sand and pebble layers that overlie sharp basal contacts with scour marks into the mud, fine upward in grain size, and have bimodal grain size distributions. Other unique features are the common occurrence of marine fossils and concentrations of heavy minerals. The occurrence of these high-energy deposits interlayered with clay-rich units indicates the coarse clastics are anomalous because they …


New Borehole Breakout Derived Stress Constraints And Their Implications For Stress Heterogeneity Near High Risk Fault Systems In The Santa Barbara Channel, Southern California, Edward Harris Pritchard Oct 2018

New Borehole Breakout Derived Stress Constraints And Their Implications For Stress Heterogeneity Near High Risk Fault Systems In The Santa Barbara Channel, Southern California, Edward Harris Pritchard

LSU Master's Theses

The Santa Barbara Channel represents the offshore portion of the Ventura Basin in Southern California. Ongoing transpression related to a regional left step in the San Andreas Fault has led to the formation of E-W trending en-echelon fault systems, with both north and south dips, which accommodate varying rates of localized shortening across the basin. Recent studies have suggested that faults within the northern region of the channel could be capable of a multisegment rupture and producing a Mw 7.78.1 tsunamigenic earthquake. However, dynamic rupture models producing these results have not accounted for stress heterogeneity, which is …


Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman Jul 2018

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use …


3-D Reconstructions And Numerical Simulations Of Precarious Rocks In Southern California, Christine E. Wittich, Tara C. Hutchinson, J. Desanto, D. Sandwell Jun 2018

3-D Reconstructions And Numerical Simulations Of Precarious Rocks In Southern California, Christine E. Wittich, Tara C. Hutchinson, J. Desanto, D. Sandwell

Department of Civil and Environmental Engineering: Faculty Publications

Reliable estimates of seismic hazard are essential for the development of resilient communities; however, estimates of rare, yet high intensity earthquakes are highly uncertain due to a lack of observations and recordings. Lacking this data, seismic hazard analyses may be based on extrapolations from earthquakes with more moderate return periods, which can lead to physically unrealistic earthquake scenarios. However, the existence of certain precariously balanced rocks (PBRs) has been identified as an indicator of an upper bound ground motion, which precludes toppling of the balanced rock, over its lifetime. To this end, a survey of PBRs was conducted in proximity …


Characterizing Coseismic Ionospheric Disturbance For Surface-Rupturing Earthquakes, Rebekah Faith Lee Dec 2017

Characterizing Coseismic Ionospheric Disturbance For Surface-Rupturing Earthquakes, Rebekah Faith Lee

Boise State University Theses and Dissertations

Coseismic ionospheric disturbances (CID) are commonly identified using global navigation space system (GNSS) satellites. Little research, however, has focused on using total electron content (TEC) observations to characterize acoustic sources on Earth's surface. For this thesis, I investigate the applicability of an analytical method to invert the TEC for the acoustic wave. The inversion is based on the modeling of a transfer function. Deconvolving the TEC by the transfer function gives the acoustic wave. Inverting for the acoustic wave in this way would remove phase differences in the TEC created by atmospheric-ionospheric coupling. I test the assumption in the model …


Assessment Of Earthquake Site Amplification And Application Of Passive Seismic Methods For Improved Site Classification In The Greater Vancouver Region, British Columbia, Frederick Andrew Jackson Sep 2017

Assessment Of Earthquake Site Amplification And Application Of Passive Seismic Methods For Improved Site Classification In The Greater Vancouver Region, British Columbia, Frederick Andrew Jackson

Electronic Thesis and Dissertation Repository

There is renewed interest to improve seismic microzonation mapping in Greater Vancouver, British Columbia (BC). We investigate local geology as the cause of observed variable ground shaking from the 2015 M 4.7 Vancouver Island earthquake. We observe high amplification at 4-6 Hz on thick sediment and the northern edge of the Fraser River delta, and disparities with current regional seismic microzonation mapping. Site amplification and shear-wave velocity (VS) are assessed from the first borehole earthquake recordings in BC. We also perform ambient vibration analyses at 13 new locations in southwest BC to highlight suitability of passive seismic methods …


Aeromagnetic, Gravity, And Differential Interferometric Synthetic Aperture Radar Analyses Reveal The Causative Fault Of The 3 April 2017 MW 6.5 Moiyabana, Botswana, Earthquake, Folarin Kolawole, Estella A. Atekwana, S. Malloy, Dorothy Sarah Stamps, Raphael Grandin, Mohamed G. Abdel Salam, Khumo Leseane, Elisha M. Shemang Sep 2017

Aeromagnetic, Gravity, And Differential Interferometric Synthetic Aperture Radar Analyses Reveal The Causative Fault Of The 3 April 2017 MW 6.5 Moiyabana, Botswana, Earthquake, Folarin Kolawole, Estella A. Atekwana, S. Malloy, Dorothy Sarah Stamps, Raphael Grandin, Mohamed G. Abdel Salam, Khumo Leseane, Elisha M. Shemang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

On 3 April 2017, a Mw 6.5 earthquake struck Moiyabana, Botswana, nucleating at >20 km focal depth within the Paleoproterozoic Limpopo-Shashe orogenic belt separating the Archean Zimbabwe and Kaapvaal Cratons. We investigate the lithospheric structures associated with this earthquake using high-resolution aeromagnetic and gravity data integrated with Differential Interferometric Synthetic Aperture Radar (DInSAR) analysis. Here we present the first results that provide insights into the tectonic framework of the earthquake. The ruptured fault trace delineated by DInSAR aligns with a distinct NW striking and NE dipping magnetic lineament within the Precambrian basement. The fault plane solution and numerical modeling …


Constraining The Spatial Extent Of Strain Localization At The Base Of The Seismogenic Zone: A Case Study From The Sandhill Corner Shear Zone, Maine, Usa, Erik Kristian Anderson Jul 2017

Constraining The Spatial Extent Of Strain Localization At The Base Of The Seismogenic Zone: A Case Study From The Sandhill Corner Shear Zone, Maine, Usa, Erik Kristian Anderson

Electronic Theses and Dissertations

Knowledge of the structure and processes of strain localization at the base of the seismogenic zone can provide constraints on the rheologic evolution of shear zones at depth and the spatial extent that seismicity influences the surrounding rock. Such knowledge is hindered by limitations of borehole measurements from such depths and a lack of structural/mineralogical preservation of original rock fabric. The Sandhill Corner Shear Zone, Maine, USA provides an opportunity to study well-preserved structures relating to strain localization along major faults exhumed from seismogenic depths. In south-central Maine, this shear zone juxtaposes two rock types: the Cape Elizabeth Formation and …


Developing And Testing A Model Of Site Amplification For Southern Ontario, Sebastian Braganza May 2017

Developing And Testing A Model Of Site Amplification For Southern Ontario, Sebastian Braganza

Electronic Thesis and Dissertation Repository

Commonly-applied methods to estimate ground-motion amplification for earthquake hazard applications in southern Ontario are highly generalized. Site amplification effects have typically been estimated by a parameter that is not well-known in the region, the time-averaged shear-wave velocity in the top 30 metres of soil; VS30. Moreover, VS30 is not well correlated with site amplification in this region. This study develops a model that can better estimate ground motions and shaking intensities in southern Ontario based on readily-available information. The model is based on a site’s peak response frequency (fpeak), which can be estimated from depth-to-bedrock. …


Pressure Dependence Of Polycrystalline Magnesite And Dolomite, Cole Blasko Jan 2017

Pressure Dependence Of Polycrystalline Magnesite And Dolomite, Cole Blasko

Williams Honors College, Honors Research Projects

Intermediate depth (170-400 km) deep focus earthquakes are observed in subducting slabs, but unlike shallow (50-170 km) and deep (400-660 km) deep focus earthquakes, the mechanism(s) responsible for them are not clear. Two common alteration products observed in peridotites, magnesite and dolomite, are stable along the pressure-temperature path of a subducting slab. Low pressure experiments indicate that these minerals are weaker than olivine, but there are no data about the pressure dependence of the strength of magnesite or dolomite. Magnesite and dolomite cylinders (1mm by 1mm) were deformed in stacked series to 25-30% strain using the deformation-DIA (DDIA) at Argonne …


Scott Marshall.Jpg, Scott Marshall Dec 2016

Scott Marshall.Jpg, Scott Marshall

Dr. Scott Marshall

No abstract provided.


2015 Gsa International Distinguished Lecturer Tours Key Locations In Central And South America, Lisa L. Ely Jul 2016

2015 Gsa International Distinguished Lecturer Tours Key Locations In Central And South America, Lisa L. Ely

Geological Sciences Faculty Scholarship

As the International Lecturer from North America, I visited 11 destinations in Ecuador, Peru, Chile, Costa Rica, Mexico, and Puerto Rico. The tour was designed to include locations where the topic of my presentation, “Following in the Footsteps of Darwin:
Combining Geological and Historical Evidence to Assess Earthquakes and Tsunami Hazards,” would have direct relevance.


Earthquakes And Seismology, John J. Renton, Thomas Repine Jan 2016

Earthquakes And Seismology, John J. Renton, Thomas Repine

Readings and Notes

The great majority of earthquakes are caused by the movement of faults. Two terms are used to determine the location of an earthquake, focus and epicenter. The focus of an earthquake is the point along a fault where the rocks slipped and released the energy previously stored during the elastic phase of deformation. Because faults represent brittle deformation, the highest frequency of earthquakes occurs at Earth's surface and decreases with depth as rocks become less brittle and more plastic. The deepest earthquake foci occur at depths of about 640 km. ( 400 mi.) which is the deepest penetration of subducting …


Earthquakes, John J. Renton, Thomas Repine Jan 2016

Earthquakes, John J. Renton, Thomas Repine

Readings and Notes

For centuries, earth scientists have known where the major earthquakes occurred. They also knew they occurred in the same locales as the most violent volcanoes, a fact that led to centuries of arguments as to which was the cause of the other. Now we know that they are not cause and effect; they are both associated with the convergent plate margins. During the mid-1900s, another major zone of both volcanic and earthquake activity was discovered, namely the divergent margins, the most important site being the oceanic ridges. Since then, we have also come to understand the occurrence of volcanic activity …


The Structural Analysis Of Enola And Greenbrier, Arkansas Earthquake Swarms: Cause And Effect?, Minella Majenu Dec 2015

The Structural Analysis Of Enola And Greenbrier, Arkansas Earthquake Swarms: Cause And Effect?, Minella Majenu

Graduate Theses and Dissertations

Almost 20 years after the remarkable earthquake swarm of 1982, near the town of Enola, Arkansas, with more than 40,000 micro-earthquakes, another event revisited the same North-Central Arkansas region in 2001. Nine years later, in 2010, a huge swarm event shook the northern part of Faulkner County, around the city of Guy. The following year, this seismic swarm event apparently migrated southward towards the city of Greenbrier, with an increase in the number of yearly recorded events. A 13km previously unrecognized, NE trending Guy-Greenbrier basement fault was revealed as a result of these swarm events.

Within the vicinity of the …


Laboratory Manual For Introductory Geology, Bradley Deline, Randa Harris, Karen Tefend Oct 2015

Laboratory Manual For Introductory Geology, Bradley Deline, Randa Harris, Karen Tefend

Geological Sciences and Geography Open Textbooks

This textbook is a comprehensive lab manual for the core curriculum Introductory Geosciences classes with both informational content and laboratory exercises. Topics include basic laws and theories in Geology, the Earth's interior and plate tectonics, water and climate change, igneous rocks and volcanoes, and earthquakes.

Accessible files with optical character recognition (OCR) and auto-tagging provided by the Center for Inclusive Design and Innovation.


Slip Pulse And Resonance Of The Kathmandu Basin During The 2015 Gorkha Earthquake, Nepal, John Galetzka, Walter Szeliga Sep 2015

Slip Pulse And Resonance Of The Kathmandu Basin During The 2015 Gorkha Earthquake, Nepal, John Galetzka, Walter Szeliga

All Faculty Scholarship for the College of the Sciences

Detailed geodetic imaging of earthquake ruptures enhances our understanding of earthquake physics and associated ground shaking. The 25 April 2015 moment magnitude 7.8 earthquake in Gorkha, Nepal was the first large continental megathrust rupture to have occurred beneath a high-rate (5-hertz) Global Positioning System (GPS) network. We used GPS and interferometric synthetic aperture radar data to model the earthquake rupture as a slip pulse ~20 kilometers in width, ~6 seconds in duration, and with a peak sliding velocity of 1.1 meters per second, which propagated toward the Kathmandu basin at ~3.3 kilometers per second over ~140 kilometers. The smooth slip …


Recent Seismicity And Regional Extension Aithin Southwestern Montana, Usa, Jessica Szkody Aug 2015

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 …


The Unusual Temporal And Spatial Slip History Of The Wassuk Range Normal Fault, Western Nevada (Usa): Implications For Seismic Hazard And Walker Lane Deformation, Benjamin Surpless, Glenn Kroeger Jun 2015

The Unusual Temporal And Spatial Slip History Of The Wassuk Range Normal Fault, Western Nevada (Usa): Implications For Seismic Hazard And Walker Lane Deformation, Benjamin Surpless, Glenn Kroeger

Benjamin E Surpless

We document temporal and spatial variations in vertical displacement rate across 6 temporal orders of magnitude to better under stand how the 100-km-long, east-dipping Wassuk Range normal fault system has accommodated strain in the context of the Walker Lane, a tectonically active, NNWtrending zone of dextral and extensional deformation that affects significant portions of western Nevada and eastern California. We combine 10Be and 26Al cosmonuclide exposure ages with shallow seismic and gravity data from the buried hanging wall of the Wassuk fault to derive a post-113 ka (105 yr time scale) vertical displacement rate of 0.82 ± 0.16 mm/yr. We …


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

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 …


The Unusual Temporal And Spatial Slip History Of The Wassuk Range Normal Fault, Western Nevada (Usa): Implications For Seismic Hazard And Walker Lane Deformation, Benjamin E. Surpless, Glenn C. Kroeger May 2015

The Unusual Temporal And Spatial Slip History Of The Wassuk Range Normal Fault, Western Nevada (Usa): Implications For Seismic Hazard And Walker Lane Deformation, Benjamin E. Surpless, Glenn C. Kroeger

Geosciences Faculty Research

We document temporal and spatial variations in vertical displacement rate across 6 temporal orders of magnitude to better under stand how the 100-km-long, east-dipping Wassuk Range normal fault system has accommodated strain in the context of the Walker Lane, a tectonically active, NNWtrending zone of dextral and extensional deformation that affects significant portions of western Nevada and eastern California. We combine 10Be and 26Al cosmonuclide exposure ages with shallow seismic and gravity data from the buried hanging wall of the Wassuk fault to derive a post-113 ka (105 yr time scale) vertical displacement rate of 0.82 ± …


Dynamic Triggering In The Coso Geothermal Field, 2004-2013, Richard A. Alfaro-Diaz Jan 2015

Dynamic Triggering In The Coso Geothermal Field, 2004-2013, Richard A. Alfaro-Diaz

Open Access Theses & Dissertations

We take advantage of EarthScope’s USArray Transportable Array (TA), regional seismic networks to investigate 154 M ≥ 7 earthquakes over a ten-year period (2004- 2013), in search of remotely triggered seismicity within the continental United States. We conduct an automated search to detect high frequency signals (which may indicate triggering of small local earthquakes) using a time window of 5 hours before and after each mainshock. The automated detection applies a short-term average (STA) to long-term-average (LTA) algorithms, to create a catalogue of detections. Using the catalog we search for an increase in detection rates after each main-shock. Sharp increases …


The Extraordinary Voyage Of Kamome; A Tsunami Boat Comes Home, Lori Dengler, Amya Miller, Amy Uyeki Jan 2015

The Extraordinary Voyage Of Kamome; A Tsunami Boat Comes Home, Lori Dengler, Amya Miller, Amy Uyeki

Trade & Scholarly Monographs

This sweet story, intended for lower elementary grades, is intended to provide a window for discussing earthquakes, tsunamis, marine debris, preparedness and cultural awareness in the classroom and within families.

On April 7, 2013, a little over two years after the magnitude 9 Tohoku-oki Japan earthquake triggered a massive tsunami off the coast of northeastern Japan, a lone boat washed up on the shores of Crescent City, California. The confirmation of the boat as belonging to a high school in Rikuzentakata was first step in an amazing story that has linked two tsunami-vulnerable communities on opposite sides of the Pacific …


Analyst A: Alternatives In Analysis Of The Utexas1 Surface Wave Dataset, Paul Michaels Dec 2014

Analyst A: Alternatives In Analysis Of The Utexas1 Surface Wave Dataset, Paul Michaels

Paul Michaels

In February of 2011 an earthquake event caused significant damage and loss of life in Christchurch, New Zealand. Such an event serves as motivation for improved foundation design and characterization of the shallow subsurface. In January of 2013, University of Texas engineers acquired surface wave data which has been made available to the ASCE GeoInstitute Geophysical Engineering Committee for a benchmark project. Participants were invited to process and interpret the common data set. This paper reports the results designated as those of "Analyst A". The active vibroseis and sledgehammer data were combined to produce a composite Rayleigh wave dispersion curve. …