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Arthur D. Frankel

Publications and source records attributed to Arthur D. Frankel.

At least 91 records · Page 5Linked to original sources
USGS2005

Seismic-hazard maps for the conterminous United States

This publication consists of six map sheets (titles and text included in this document, below), geospatial datasets, and metadata. The geospatial datasets consist of ArcInfo export files for the seismic-hazard point and polygon data shown on the sheets. Probabilistic seismic-hazard maps were prepared for the conterminous United States portraying peak horizontal acceleration and horizontal spectral response acceleration for 0.2- and 1.0-second periods with probabilities of exceedance of 10 percent in 50 years and 2 percent in 50 years. All of the maps were prepared by combining the hazard derived from spatially smoothed historic seismicity with the 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 to the boundary between NEHRP (National Earthquake Hazards Reduction program) site classes B and C. This data set represents the results of calculations of hazard curves for a grid of points with a spacing of 0.05 degrees in latitude and longitude. The points were contoured to produce the final representation of the seismic hazard.

Scientific Investigations Map↗
USGS2004

Comments on potential geologic and seismic hazards affecting coastal Ventura County, California

This report examines the regional seismic and geologic hazards that could affect proposed liquefied natural gas (LNG) facilities in coastal Ventura County, California. Faults throughout this area are thought to be capable of producing earthquakes of magnitude 6.5 to 7.5, which could produce surface fault offsets of as much as 15 feet. Many of these faults are sufficiently well understood to be included in the current generation of the National Seismic Hazard Maps; others may become candidates for inclusion in future revisions as research proceeds. Strong shaking is the primary hazard that causes damage from earthquakes and this area is zoned with a high level of shaking hazard. The estimated probability of a magnitude 6.5 or larger earthquake (comparable in size to the 2003 San Simeon quake) occurring in the next 30 years within 30 miles of Platform Grace is 50-60%; for Cabrillo Port, the estimate is a 35% likelihood. Combining these probabilities of earthquake occurrence with relationships that give expected ground motions yields the estimated seismic-shaking hazard. In parts of the project area, the estimated shaking hazard is as high as along the San Andreas Fault. The combination of long-period basin waves and LNG installations with large long-period resonances potentially increases this hazard.

California↗
USGS2002

Implosion, earthquake, and explosion recordings from the 2000 Seattle Kingdome Seismic Hazards Investigation of Puget Sound (SHIPS), Washington

This report describes seismic data obtained in Seattle, Washington, March 24-28, 2000, during a Seismic Hazards Investigation of Puget Sound (SHIPS). The seismic recordings obtained by this SHIPS experiment, nicknamed Kingdome SHIPS, were designed to (1) measure site responses throughout Seattle and to (2) help define the location of the Seattle fault. During Kingdome SHIPS, we recorded the Kingdome implosion, four 150-lb (68-kg) shots, and a M w = 7.6 teleseism using a dense network of seismographs deployed throughout Seattle. The seismographs were deployed at a nominal spacing of 1 km in a hexagonal grid extending from Green Lake in the north to Boeing Field in the south. The Seattle Kingdome was a domed sports stadium located in downtown Seattle near the Seattle fault. The Seattle Kingdome was imploded (demolished) at 8:32 AM local time (16:32 UTC) on March 26 (JD 086), 2000. The seismic energy produced by implosion of the Kingdome was equivalent to a local earthquake magnitude of 2.3. Strong impacts produced by the implosion of the Kingdome generated seismic arrivals to frequencies as low as 0.1 Hz. Two shots located north of the Seattle fault, where the charges were detonated within the ground water column (Discovery and Magnuson Parks), were much more strongly coupled than were the two shots to the south of the Seattle fault, where the shots were detonated above the water table (Lincoln and Seward Parks). Thirty-eight RefTek stations, scattered throughout Seattle, recorded the M w = 7.6 Japan Volcano Islands earthquake (22.4°N, 143.6°E, 104 km depth) of 28 March 2000 (JD 088). This teleseism produced useful signals for periods between 4 and 7 seconds. Only a few recordings of small magnitude local earthquakes were made, and these recordings are not presented. In this report, we describe the acquisition of these data, discuss the processing and merging of the data into common shot gathers, and illustrate the acquired data. We also describe the format and content of the archival tapes containing the SEGY-formatted, common-shot gathers.

Washington↗
USGS2002

Investigation of an earthquake swarm near Trinidad, Colorado, August-October 2001

A swarm of 12 widely felt earthquakes occurred between August 28 and September 21, 2001, in the area west of the town of Trinidad, Colorado. The earthquakes ranged in magnitude between 2.8 and 4.6, and the largest event occurred on September 5, eight days after the initial M 3.4 event. The nearest permanent seismograph station to the swarm is about 290 km away, resulting in large uncertainties in the location and depth of these events. To better locate and characterize the earthquakes in this swarm, we deployed a total of 12 portable seismographs in the area of the swarm starting on September 6. Here we report on data from this portable network that was recorded between September 7 and October 15. During this time period, we have high-quality data from 39 earthquakes. The hypocenters of these earthquakes cluster to define a 6 km long northeast-trending fault plane that dips steeply (70-80?) to the southeast. The upper bound of well-constrained hypocenters is near 3 km depth and lower bound is near 6 km depth. Preliminary fault mechanisms suggest normal faulting with movement down to the southeast. Significant historical earthquakes have occurred in the Trinidad region in 1966 and 1973. Reexamination of felt reports from these earthquakes suggest that the 1973 events may have occurred in the same area, and possibly on the same fault, as the 2001 swarm. In recent years, a large volume of excess water that is produced in conjunction with coal-bed methane gas production has been returned to the subsurface in fluid disposal wells in the area of the earthquake swarm. Because of the proximity of these disposal wells to the earthquakes, local residents and officials are concerned that the fluid disposal might have triggered the earthquakes. We have evaluated the characteristics of the seismicity using criteria proposed by Davis and Frohlich (1993) as diagnostic of seismicity induced by fluid injection. We conclude that the characteristics of the seismicity and the fluid disposal process do not constitute strong evidence that the seismicity is induced by the fluid disposal, though they do not rule out this possibility.

Colorado↗
USGS2000

Preliminary simulation of a M6.5 earthquake on the Seattle Fault using 3D finite-difference modeling

A three-dimensional finite-difference simulation of a moderate-sized (M 6.5) thrust-faulting earthquake on the Seattle fault demonstrates the effects of the Seattle Basin on strong ground motion in the Puget lowland. The model area includes the cities of Seattle, Bremerton and Bellevue. We use a recently developed detailed 3D-velocity model of the Seattle Basin in these simulations. The model extended to 20-km depth and assumed rupture on a finite fault with random slip distribution. Preliminary results from simulations of frequencies 0.5 Hz and lower suggest amplification can occur at the surface of the Seattle Basin by the trapping of energy in the Quaternary sediments. Surface waves generated within the basin appear to contribute to amplification throughout the modeled region. Several factors apparently contribute to large ground motions in downtown Seattle: (1) radiation pattern and directivity from the rupture; (2) amplification and energy trapping within the Quaternary sediments; and (3) basin geometry and variation in depth of both Quaternary and Tertiary sediments

Open-File Report↗
USGS1999

Seismic-hazard maps for Alaska and the Aleutian Islands

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 horizontal spectral response acceleration for 1.0 second period 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 to the boundary between NEHRP site classes B and C. This data set represents the results of calculations of hazard curves for a grid of points with a spacing of 0.1 degrees in latitude and longitude. The grid of points were contoured to produce the final representation of the seismic-hazard.

IMAP↗
USGS1999

Seismic and tsunami hazard in Puerto Rico and the Virgin Islands

Executive Summary Puerto Rico and the Virgin Islands are located at an active plate boundary between the North American plate and the northeast corner of the Caribbean plate. The region was subject in historical times to large magnitude earthquakes and devastating tsunamis. A major downward tilt of the sea floor north of Puerto Rico and the Virgin Islands, large submarine rockslides, and an unusually large negative gravity anomaly are also indicative of a tectonically active region. Scientists have so far failed to explain the deformation of this region in a coherent and predictable picture, such as in California, and this has hampered their ability to assess seismic and tsunami hazards in the region. The NE corner of the Caribbean is unique among the seismically-active regions of the United States in that it is mostly covered by water. This fact presents an additional challenge for seismic and tsunami hazard assessment and mitigation. The workshop, convened in San Juan on March 23-24, 1999, was "historic" in that it brought together for the first time a broad spectrum of scientists, engineers, and public and private sector officials who deal with such diverse questions as tectonic models, probabilistic assessment of seismic hazard, prediction of tsunami runup, strong ground motion, building codes, stability of man-made structures, and the public’s preparedness for natural disasters. It was an opportunity for all the participants to find out how their own activity fit into the broad picture of science and how it aids society in hazard assessment and mitigation. In addition, the workshop was offered as a continuing education course at the Colegio de Ingenieros y Agrimensores de Puerto Rico, which assured a rapid dissemination of the results to the local community. A news conference which took place during the workshop alerted the public to the efforts of the USGS, other Federal agencies, the Commonwealth of Puerto Rico, universities and the private sector. During the first day of the workshop, participants from universities, federal institutions, and consulting firms in Puerto Rico, the Virgin Islands, the continental U.S., Dominican Republic, and Europe reviewed the present state of knowledge including a review and discussion of present plate models, recent GPS and seismic reflection data, seismicity, paleoseismology, and tsunamis. The state of earthquake/tsunami studies in Puerto Rico was presented by several faculty members from the University of Puerto Rico at Mayaguez. A preliminary seismic hazard map was presented by the USGS and previous hazard maps and economic loss assessments were considered. During the second day, the participants divided into working groups and prepared specific recommendations for future activities in the region along the six following topics below. Highlights of these recommended activities are: Marine geology and geophysics – Acquire deep-penetration seismic reflection and refraction data, deploy temporary ocean bottom seismometer arrays to record earthquakes, collect high-resolution multibeam bathymetry and side scan sonar data of the region, and in particular, the near shore region, and conduct focussed high-resolution seismic studies around faults. Determine slip rates of specific offshore faults. Assemble a GIS database for available marine geological and geophysical data. Paleoseismology and active faults - Field reconnaissance aimed at identifying Quaternary faults and determining their paleoseismic chronology and slip rates, as well as identifying and dating paleoliquefaction features from large earthquakes. Quaternary mapping of marine terraces, fluvial terraces and basins, beach ridges, etc., to establish framework for understanding neotectonic deformation of the island. Interpretation of aerial photography to identify possible Quaternary faults. Earthquake seismology – Determine an empirical seismic attenuation function using observations from local seismic networks and recently-installed broad-band stations. Evaluate existing earthquake catalogs from local networks and regional stations, complete the catalogs. Transcribe the pre-1991 network data from 9-track tape onto more stable archival media. Calibrate instruments of local networks. Use GPS measurement to constrain deformation rates used in seismic-hazard maps. Engineering – Prepare liquefaction susceptibility maps for the urban areas. Update and improve databases for types of site conditions. Collect site effect observations and near-surface geophysical measurements for future local (urban-area) hazard maps. Expand the number of instruments in the strong motion program. Develop fragility curves for Puerto Rico construction types and details, and carry out laboratory testing on selected types of mass-produced construction. Consider tsunami design in shoreline construction projects. Tsunami hazard - Extract tsunami observations from archives and develop a Caribbean historical tsunami database. Analyze prehistoric tsunami deposits. Collect accurate, up-to-date, near-shore topography and bathymetry for accurate inundation models. Prepare tsunami flooding and evacuation maps. Establish a Caribbean Tsunami Warning System for Puerto Rico and the Virgin Islands. Evaluate local, regional, national, and global seismic networks and equipment, and their role in a tsunami warning system. Societal concerns – Prepare warning messages, protocols, and evacuation routes for earthquake, tsunami, and landslide hazards for Puerto Rico and the U.S. Virgin Islands. Advocate enforcement of existing building codes. Prepare non-technical hazard assessment maps for political and educational uses. Raise the awareness of potentially affected populations by presentations at elementary schools, by the production of a tsunami video, and by distribution of earthquake preparedness manuals in newspaper supplements. Promote partnerships at state and federal level for long-term earthquake and tsunami hazard mitigation. This partnership should also include the private sector such as the insurance industry, telecommunication companies, and the engineering community. The following reports of the various working groups are the cumulative recommendations of the community of scientists, engineers, and public officials, who participated in the workshop. The list of participants and the workshop’s agenda are given in the appendix. Marine and Geology and Geophysics Working Group Paleoseismology and Active Faults Working Group Joint Working Group for Earthquake Seismology and Engineering Tsunami Working Group Societal Concerns Working Group

Puerto Rico and the Virgin Islands↗
USGS1996

National Seismic-Hazard Maps: Documentation June 1996

In this release of hazard maps we present numerous maps and data with varying parameters. The computations for these maps and data used 50 year return periods on firm rock at 760 m/sec. All of the maps were prepared by combining hazard derived from spatially- smoothed historic seismicity with hazard from fault-specific sources. For more information please read our full documentation. Although these maps have been used by the U.S. Geological Survey, no warranty, expressed or implied is made by the USGS as to the accuracy of the maps and related material nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith.

Open-File Report↗
USGS1996

Site-response maps for the Los Angeles region based on earthquake ground motions

Ground-motion records from aftershocks of the 1994 Northridge earthquake and main-shock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response in the urban Los Angeles, California, area. Two frequency bands are considered, 0.5-1.5 Hz and 2.0-6.0 Hz. Instrument characteristics prevented going to lower frequencies, and frequencies above 6.0 Hz are less important to the building inventory. Site response determined at the instrumented locations is associated with the surficial geology and contoured to produce a continuous spatial estimation of site response. The maps in this report are preliminary and will evolve as more data become available and more analysis is done.

California↗
USGS1994

The Loma Prieta, California, Earthquake of October 17, 1989: Strong ground motion

Strong ground motion generated by the Loma Prieta, Calif., earthquake (MS~7.1) of October 17, 1989, resulted in at least 63 deaths, more than 3,757 injuries, and damage estimated to exceed $5.9 billion. Strong ground motion severely damaged critical lifelines (freeway overpasses, bridges, and pipelines), caused severe damage to poorly constructed buildings, and induced a significant number of ground failures associated with liquefaction and landsliding. It also caused a significant proportion of the damage and loss of life at distances as far as 100 km from the epicenter. Consequently, understanding the characteristics of the strong ground motion associated with the earthquake is fundamental to understanding the earthquake's devastating impact on society. The papers assembled in this chapter address this problem. Damage to vulnerable structures from the earthquake varied substantially with the distance from the causative fault and the type of underlying geologic deposits. Most of the damage and loss of life occurred in areas underlain by 'soft soil'. Quantifying these effects is important for understanding the tragic concentrations of damage in such areas as Santa Cruz and the Marina and Embarcadero Districts of San Francisco, and the failures of the San Francisco-Oakland Bay Bridge and the Interstate Highway 880 overpass. Most importantly, understanding these effects is a necessary prerequisite for improving mitigation measures for larger earthquakes likely to occur much closer to densely urbanized areas in the San Francisco Bay region. The earthquake generated an especially important data set for understanding variations in the severity of strong ground motion. Instrumental strong-motion recordings were obtained at 131 sites located from about 6 to 175 km from the rupture zone. This set of recordings, the largest yet collected for an event of this size, was obtained from sites on various geologic deposits, including a unique set on 'soft soil' deposits (artificial fill and bay mud). These exceptional ground-motion data are used by the authors of the papers in this chapter to infer radiation characteristics of the earthquake source, identify dominant propagation characteristics of the Earth?s crust, quantify amplification characteristics of near-surface geologic deposits, develop general amplification factors for site-dependent building-code provisions, and revise earthquake-hazard assessments for the San Francisco Bay region. Interpretations of additional data recorded in well-instrumented buildings, dams, and freeway overpasses are provided in other chapters of this report.

California↗
USGS1990

Source parameters for small events associated with the 1986 North Palm Springs, California, earthquake determined using empirical Green functions

Using small events as empirical Green functions, which include path, site, and instrument effects on the P waveforms, source parameters were estimated for 25 M L 3.4 to 4.4 events associated with the 1986 North Palm Springs earthquake. The static stress drops ranged from 3 to 80 bars, for moments of 0.7 to 11 × 10 21 dyne-cm. There was a spatial pattern to the stress drops of the aftershocks which showed increasing values along the fault plane toward the northwest compared to relatively low values near the hypocenter of the mainshock. The highest values were outside the main area of slip, and are believed to reflect a loaded area of the fault that still has an higher level of stress which was not released during the main shock. The relatively high stress drop of a preshock in 1983, located close to the hypocenter of the main shock, is also interpreted as evidence that stress drops of magnitude 3 and 4 events can be used as indicators of the stress level in a particular area.

California↗