Publications
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A note on adding viscoelasticity to earthquake simulators
Here, I describe how time‐dependent quasi‐static stress transfer can be implemented in an earthquake simulator code that is used to generate long synthetic seismicity catalogs. Most existing seismicity simulators use precomputed static stress interaction coefficients to rapidly implement static stress transfer in fault networks with typically tens of thousands of fault patches. The extension to qu
Authors
Fred Pollitz
System identification based on deconvolution and cross correlation: An application to a 20‐story instrumented building in Anchorage, Alaska
Deconvolution and cross‐correlation techniques are used for system identification of a 20‐story steel, moment‐resisting frame building in downtown Anchorage, Alaska. This regular‐plan midrise structure is instrumented with a 32‐channel accelerometer array at 10 levels. The impulse response functions (IRFs) and correlation functions (CFs) are computed based on waveforms recorded from ambient vibrat
Authors
Weiping Wen, Erol Kalkan
Spatio-temporal mapping of plate boundary faults in California using geodetic imaging
The Pacific–North American plate boundary in California is composed of a 400-km-wide network of faults and zones of distributed deformation. Earthquakes, even large ones, can occur along individual or combinations of faults within the larger plate boundary system. While research often focuses on the primary and secondary faults, holistic study of the plate boundary is required to answer several fu
Authors
Andrea Donnellan, Ramon Arrowsmith, Stephen B. DeLong
Magnetic monitoring in Saguaro National Park
On a sandy, arid plain, near the Rincon Mountain Visitor Center of Saguaro National Park, tucked in among brittlebush, creosote, and other hardy desert plants, is an unusual type of observatory—a small unmanned station that is used for monitoring the Earth’s variable magnetic field. Named for the nearby city of Tucson, Arizona, the observatory is 1 of 14 that the Geomagnetism Program of the U.S.
Authors
Jeffrey J. Love, Carol Finn, Yesenia C. Gamez Valdez, Don Swann
The morphology of transverse aeolian ridges on Mars
A preliminary survey of publicly released high resolution digital terrain models (DTMs) produced by the High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter identified transverse aeolian ridges (TARs) in 154 DTMs in latitudes from 50°S to 40°N. Consistent with previous surveys, the TARs identified in HiRISE DTMs are found at all elevations, irrespective of the
Authors
Paul Geissler, Justin T. Wilgus
Geodetic slip model of the 3 September 2016 Mw 5.8 Pawnee, Oklahoma, earthquake: Evidence for fault‐zone collapse
The 3 September 2016 Mw 5.8 Pawnee earthquake in northern Oklahoma is the largest earthquake ever recorded in Oklahoma. The coseismic deformation was measured with both Interferometric Synthetic Aperture Radar and Global Positioning System (GPS), with measureable signals of order 1 cm and 1 mm, respectively. We derive a coseismic slip model from Sentinel‐1A and Radarsat 2 interferograms and GPS st
Authors
Fred Pollitz, Charles W. Wicks, Martin Schoenball, William L. Ellsworth, Mark Murray
Finite‐fault Bayesian inversion of teleseismic body waves
Inverting geophysical data has provided fundamental information about the behavior of earthquake rupture. However, inferring kinematic source model parameters for finite‐fault ruptures is an intrinsically underdetermined problem (the problem of nonuniqueness), because we are restricted to finite noisy observations. Although many studies use least‐squares techniques to make the finite‐fault problem
Authors
Brandon Clayton, Stephen H. Hartzell, Morgan P. Moschetti, Sarah E. Minson
Doubling of coastal flooding frequency within decades due to sea-level rise
Global climate change drives sea-level rise, increasing the frequency of coastal flooding. In most coastal regions, the amount of sea-level rise occurring over years to decades is significantly smaller than normal ocean-level fluctuations caused by tides, waves, and storm surge. However, even gradual sea-level rise can rapidly increase the frequency and severity of coastal flooding. So far, global
Authors
Sean Vitousek, Patrick L. Barnard, Charles H. Fletcher, Neil Frazer, Li H. Erikson, Curt D. Storlazzi
Advanced National Seismic System—Current status, development opportunities, and priorities for 2017–2027
SummaryEarthquakes pose a threat to the safety of over 143 million people living in the United States. Earthquake impacts can be significantly reduced if communities understand their risk and take proactive steps to mitigate that risk. The Advanced National Seismic System (ANSS) is a cooperative effort to collect and analyze seismic and geodetic data on earthquakes, issue timely and reliable notif
Authors
3.5 square meters: Constructive responses to natural disasters
Natural disasters and their consequences dominate the news almost on a daily basis. Quick-impact preventive and aid measures are essential for the victims to survive. This volume presents a selection of projects which demonstrate impressively how both cutting-edge technology and locally available materials and resources can be used for this purpose.
Geomorphological evidence for ground ice on dwarf planet Ceres
Five decades of observations of Ceres suggest that the dwarf planet has a composition similar to carbonaceous meteorites and may have an ice-rich outer shell protected by a silicate layer. NASA’s Dawn spacecraft has detected ubiquitous clays, carbonates and other products of aqueous alteration across the surface of Ceres, but surprisingly it has directly observed water ice in only a few areas. Her
Authors
Britney E. Schmidt, Kynan H.G. Hughson, Heather T. Chilton, Jennifer E. C. Scully, Thomas Platz, Andreas Nathues, Hanna Sizemore, Michael T. Bland, Shane Byrne, Simone Marchi, David O'Brien, Norbert Schorghofer, Harald Hiesinger, Ralf Jaumann, Jan Hendrick Pasckert, Justin D. Lawrence, Debra Buzckowski, Julie C. Castillo-Rogez, Mark V. Sykes, Paul M. Schenk, Maria-Cristina DeSanctis, Giuseppe Mitri, Michelangelo Formisano, Jian-Yang Li, Vishnu Reddy, Lucille Le Corre, Christopher T. Russell, Carol A. Raymond
Oregon OCS seafloor mapping: Selected lease blocks relevant to renewable energy
In 2014 the U.S. Geological Survey (USGS) and the Bureau of Ocean Energy Management (BOEM) entered into Intra-agency agreement M13PG00037 to map an area of the Oregon Outer Continental Shelf (OCS) off of Coos Bay, Oregon, under consideration for development of a floating wind energy farm. The BOEM requires seafloor mapping and site characterization studies in order to evaluate the impact of seaflo
Authors
Guy R. Cochrane, Lenaïg G. Hemery, Sarah K. Henkel