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A scenario represents one realization of a potential future earthquake by assuming a particular magnitude, location, and fault-rupture geometry and estimating shaking using a variety of strategies. In planning and coordinating emergency response, utilities, local government, and other organizations are best served by conducting training exercises based on realistic earthquake situations—ones similar to those they are most likely to face. ShakeMap Scenario earthquakes can fill this role. They can also be used to examine exposure of structures, lifelines, utilities, and transportation corridors to specified potential earthquakes. A ShakeMap earthquake scenario is a predictive ShakeMap with an assumed magnitude and...
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New active-source shallow seismic (shear-wave and acoustic-wave) measurements were obtained at 18 prioritized seismic monitoring station locations in the north San Francisco Bay area to measure site-specific ground motion amplification effects, soil depth, depth to bedrock (Z1.0 Vs=1 km/s), calculate site specific velocity-depth profiles and Vs30, and develop NEHRP site classifications for each location. This study was led by Principal Investigators Jamey Turner, Cooper Brossy, and Daniel O’Connell and field data were acquired by Glendon Adams and Lincoln Steele. Seismic monitoring sites that recorded high PGA values during the M6.0 Napa earthquake, proximal to higher population densities, and sites recommended...
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The data set consists of time, depth, reflection coefficient synthetic, sonic velocity, density, and amplitude used to create synthetic seismogram - City of Hollywood Utility, G-2961, (HOL-IW1), Broward County, Florida.
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Probabilistic seismic hazard maps were prepared for Alaska portraying peak horizontal ground acceleration and horizontal spectral response acceleration for 0.2, 0.3, and 1.0 second periods with probabilities of exceedance of 10% in 50 years and 2% in 50 years. This particular data set is for peak horizontal acceleration with a 10% probability of exceedance in 50 years. All of the maps were prepared by combining hazard derived from spatially-smoothed historic seismicity with hazard from fault-specific sources. The acceleration values contoured are the random horizontal component. The reference site condition is firm rock, defined as having an average shear-wave velocity of 760 m/sec in the top 30 meters corresponding...
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ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes. These maps are used by federal, state, and local organizations, both public and private, for post-earthquake response and recovery, public and scientific information, as well as for preparedness exercises and disaster planning.
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The NEIC global earthquake bulletin is called the Preliminary Determination of Epicenters or PDE, and is one of many discrete products in the ANSS Comprehensive Catalog (ComCat). We use the word "Preliminary" for our final bulletin because the Bulletin of the International Seismological Centre is considered to be the final global archive of parametric earthquake data, in other words phase arrival (“pick”) times and amplitudes.
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Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential tsunami hazards for the city of Sand Point, on Popof Island in the Shumagin Islands archipelago. We numerically modeled the extent of inundation from tsunami waves generated by local and distant earthquake sources. We considered the results in light of historical observations. The worst-case scenarios are defined by analyzing results of the sensitivity study of the tsunami dynamics with respect to different slip distributions along the Aleutian megathrust. For the Sand Point area, the worst-case scenarios are thought to be thrust earthquakes in the Shumagin Islands region with magnitudes...
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Probabilistic seismic hazard maps were prepared for Alaska portrayingpeak horizontal ground acceleration and horizontal spectral responseacceleration for 0.2, 0.3, and 1.0 second periods with probabilitiesof exceedance of 10% in 50 years and 2% in 50 years. This particulardata set is for horizontal spectral response acceleration for 0.2 secondperiod with a 2% probability of exceedance in 50 years. All ofthe maps were prepared by combining hazard derived from spatially-smoothed historic seismicity with hazard from fault-specific sources.The acceleration values contoured are the random horizontal component.The reference site condition is firm rock, defined as having an averageshear-wave velocity of 760 m/sec in the...
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This cover consists of location and size information for historicaland recent earthquakes that caused Modified Mercalli Intensity(MMI) VI (6) or higher in the map area. There were 26 earthquakesthat caused that level of damage. The most reknown are thefour earthquakes in the 1811- 1812 sequence; two on Dec 16,1811, and one each on Jan 23, 1812, and Feb 7, 1812. Theircalculated Moment Magnitudes were 8.1, 7.2, 7.8, and 8.0,respectively. The most recent damaging earthquake was on June 10,1987 near Olney, Illinois. It had a Moment Magnitude of 5.2.
Tags: earthquake occurrences, 17025 = Clay, 21145 = McCracken, 17055 = Franklin, 17047 = Edwards, All tags...
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Compiled Vs30 measurements obtained by studies funded by the U.S. Geological Survey (USGS) and other governmental agencies. Thus far, there are 2,997 sites in the United States, along with metadata for each measurement from government-sponsored reports, Web sites, and scientific and engineering journals. Most of the data originated from publications directly reporting the work of field investigators. A small subset (less than 20 percent) of Vs30 values was previously compiled by the USGS and other research institutions. Whenever possible, Vs30 originating from these earlier compilations were crosschecked against published reports. Both downhole and surface-based Vs30 estimates are represented. Most of the VS30 data...
The data from the borehole strainmeter network set consists of raw data from the telemetry, state of health measurements, environmental measurement of temperature and pressure, and processed borehole strainmeter data. For each strainmeter site in this network, there will be a mix of raw data, SOH, environmental data, and processed strain. Each channel of data consists of a time of observation, usually 10-minute intervals, and a number that is either telemetry counts (which is proportional to the voltage output by the instrument), or in units of strain, which are either in part per million or parts per billion. Processed strain will be free of glitches and other artifacts and are corrected for changes in atmospheric...
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This data release includes time-series data from a monitoring site located in a small drainage basin in the Arroyo Seco watershed in Los Angeles County, CA, USA (N3788964 E389956, UTM Zone 11, NAD83). The site was established after the 2009 Station Fire and recorded a series debris flows in the first winter after the fire. The data include three types of time-series: (1) 1-minute time series of rainfall, soil water content, channel bed pore pressure and temperature, and flow stage recorded by radar and laser distance meters (ArroyoSecoContinuous.csv); (2) 10-Hz time series of flow stage recorded by the laser distance meter during rain storms (ArroyoSecoStormLaser.csv), and (3) 2-second time series of rainfall and...
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The data set consists of time, depth, reflection coefficient synthetic, sonic velocity, density, and amplitude used to create synthetic seismogram - Deerfield Beach BHC, G-2968, Broward County, Florida.
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The data set consists of time, depth, reflection coefficient synthetic, sonic velocity, density, and amplitude used to create synthetic seismogram - City of Sunrise Utility, SUN-I3, Broward County, Florida.
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The data set consists of time, depth, reflection coefficient synthetic, sonic velocity, density, and amplitude used to create synthetic seismogram - City of Sunrise Utility, G-2981, Broward County, Florida.


map background search result map search result map Seismic-Hazard Maps for Alaska and the Aleutian Islands: PGA050 Seismic-Hazard Maps for Alaska and the Aleutian Islands: 5HZ250 Seismotectonic maps in the vicinity of the lower Wabash Valley,Illinois, Indiana, and Kentucky - Digital Spatial Database:Damaging Earthquakes G-2946 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2968 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2961 (HOL-IW1) : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-3805 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida SUN-I3 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2981 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida Post-wildfire debris-flow monitoring data, Arroyo Seco, 2009 Station Fire, Los Angeles County, California, November 2009 to March 2010. Tsunami inundation maps for the city of Sand Point, Alaska Tsunami inundation maps for the city of Sand Point, Alaska G-2946 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2968 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2961 (HOL-IW1) : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-3805 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida SUN-I3 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida G-2981 : Synthetic Seismogram Data for Correlation Between Seismic-Reflection Profiles and Well Data, Broward County, Florida Seismotectonic maps in the vicinity of the lower Wabash Valley,Illinois, Indiana, and Kentucky - Digital Spatial Database:Damaging Earthquakes Seismic-Hazard Maps for Alaska and the Aleutian Islands: PGA050 Seismic-Hazard Maps for Alaska and the Aleutian Islands: 5HZ250