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Costs and consequences of natural hazards can be enormous; each year more people and infrastructure are at risk. We develop and apply hazards science to help protect U.S. safety, security, and economic well being. These scientific observations, analyses, and research are crucial for the Nation to become more resilient to natural hazards.Read Our Science Strategy
Pulsed strain release on the Altyn Tagh fault, northwest China
Earthquake recurrence models assume that major surface-rupturing earthquakes are followed by periods of reduced rupture probability as stress rebuilds. Although purely periodic, time- or slip-predictable rupture models are known to be oversimplifications, a paucity of long records of fault slip clouds understanding of fault behavior and earthquake...Gold, Ryan D.; Cowgill, Eric; Arrowsmith, J. Ramón; Friedrich, Anke M.
An updated geospatial liquefaction model for global application
We present an updated geospatial approach to estimation of earthquake-induced liquefaction from globally available geospatial proxies. Our previous iteration of the geospatial liquefaction model was based on mapped liquefaction surface effects from four earthquakes in Christchurch, New Zealand, and Kobe, Japan, paired with geospatial explanatory...Zhu, Jing; Baise, Laurie G.; Thompson, Eric M.
Frictional strength of wet and dry montmorillonite
Montmorillonite is a common mineral in fault zones, and its low strength relative to other common gouge minerals is important in many models of fault rheology. However, the coefficient of friction, μ, varies with degree of saturation and is not well constrained in the literature due to the difficulty of establishing fully drained or fully dried...Morrow, Carolyn A.; Moore, Diane E.; Lockner, David A.
Repeatability of testing a small broadband sensor in the Albuquerque Seismological Laboratory Underground Vault
Variability in seismic instrumentation performance plays a fundamental role in our ability to carry out experiments in observational seismology. Many such experiments rely on the assumed performance of various seismic sensors as well as on methods to isolate the sensors from nonseismic noise sources. We look at the repeatability of estimating the...Ringler, Adam T.; Holland, Austin; Wilson, David C.
The 2008 Wells, Nevada earthquake sequence: Source constraints using calibrated multiple event relocation and InSAR
The 2008 Wells, NV earthquake represents the largest domestic event in the conterminous U.S. outside of California since the October 1983 Borah Peak earthquake in southern Idaho. We present an improved catalog, magnitude complete to 1.6, of the foreshock-aftershock sequence, supplementing the current U.S. Geological Survey (USGS) Preliminary...Nealy, Jennifer; Benz, Harley M.; Hayes, Gavin; Berman, Eric; Barnhart, William D.
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...Pollitz, Fred
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...Wen, Weiping; Kalkan, Erol
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...Donnellan, Andrea; Arrowsmith, Ramon; DeLong, Stephen B.
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...Love, Jeffrey J.; Finn, Carol A.; Gamez Valdez, Yesenia C.; Swann, Don
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‐...Clayton, Brandon; Hartzell, Stephen; Moschetti, Morgan P.; Minson, Sarah E.
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...Pollitz, Fred; Wicks, Charles W.; Schoenball, Martin; Ellsworth, William L.; Murray, Mark
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...Geissler, Paul; Wilgus, Justin T.
Cracking and slumping of the Halema‘uma‘u crater walls are clearly evident in this aerial view captured during HVO's overflight of Kīlauea's summit this morning. Steam plumes have been rising from within the crater, as well as from cracks adjacent to the crater.
Another aerial view showing prominent cracking around Halema‘uma‘u from the ongoing subsidence at Kīlauea's summit. The steaming cracks in the background have been observed for several days.
Dramatic changes at Halema‘uma‘u could be seen through gases rising from the crater during HVO's overflight of the summit this morning at 10 a.m. HST. The view here looks to the southwest, with the former overlook parking lot barely visible to the left of the gas plume.
HVO's early morning helicopter overflight of Kīlauea's lower East Rift Zone showed that lava continues to flow into the ocean in the vicinity of Kapoho Bay and Vacationland.
Nearshore geophysical mapping with sub-bottom sled (foreground), personal watercraft equipped with echosounders (background, water) and beach-based personnel (background, beach).
This animated GIF shows a sequence of radar amplitude images that were acquired by the Italian Space Agency's Cosmo-SkyMed satellite system. The images illustrate changes to the...
USGS teams install storm-tide sensors in Florida before Hurricane Hermine makes landfall
Old-fashioned interviews are compared to Did You Feel It? responses for this earthquake.
September is National Preparedness Month, a time to highlight the resources available to help you and your loved ones stay as safe as possible.
New research from the U.S. Geological Survey and the University of Colorado shows actions taken by drillers and regulators can lessen risk in the case of earthquakes likely caused by the injection of industrial wastewater deep underground.
New informational products about the health hazards of volcanic air pollution known as “vog,” are available through a new interagency partnership.
Reporters are invited to attend a telephone press conference on Thursday, August 18, 2016, 2:00 p.m. HST, about new informational resources regarding vog and related health concerns in Hawaii.
A new interactive map and companion report from the U.S. Geological Survey allows residents living in and around New Mexico’s Jemez Mountains to see where they’re located in relation to postwildfire debris-flow hazards.
During what months is hurricane season typically recognized along the Atlantic Coast?
Twenty middle-school girls from Washington and Oregon are participating in the second annual “GeoGirls” outdoor volcano science program at Mount St. Helens, jointly organized by the U.S. Geological Survey and the Mount St. Helens Institute.