Publications
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A direct method for calculating instrument noise levels in side-by-side seismometer evaluations
The subject of determining the inherent system noise levels present in modem broadband closed loop seismic sensors has been an evolving topic ever since closed loop systems became available. Closed loop systems are unique in that the system noise can not be determined via a blocked mass test as in older conventional open loop seismic sensors. Instead, most investigators have resorted to performing
Authors
L. Gary Holcomb
Earthquakes & Volcanoes, Volume 21, Number 1, 1989: Featuring the U.S. Geological Survey's National Earthquake Information Center in Golden, Colorado, USA
Earthquakes and Volcanoes is published bimonthly by the U.S. Geological Survey to provide current information on earthquakes and seismology, volcanoes, and related natural hazards of interest to both generalized and specialized readers. The Secretary of the Interior has determined that the publication of this periodical is necessary in the transaction of the public business required by law of this
Authors
Henry Spall, Diane C. Schnabel
A broad-band, wide-dynamic range, strong-motion array near Parkheld, California, USA for measurement of acceleration and volumetric strain
No abstract available.
Authors
Roger D. Borcherdt, Malcolm J. S. Johnston, Thomas Noce, Gary Glassmoyer, Douglas Myren
Vertical seismic profiling of Oroville microearthquakes: Velocity spectra and particle motion as a function of depth
Direct evidence of site distortion of P- and S-wave microearthquake source spectra at Oroville, California, is presented. The data were gathered by placing vertical and three-component seismometers at 90 m intervals in a 500 m borehole through the Cleveland Hill normal fault, on which the 1975, ML = 5.7 Oroville earthquake took place. High-pressure, hydraulic locking mechanisms were used to firmly
Authors
P. E. Malin, J. A. Waller, Roger D. Borcherdt, E. Cranswick, Edward G. Jensen, J. Van Schaak
Friction of ice
The frictional strength of ice seems to be well below that for all other rocks. Triaxial testing of cylinders of pure water ice containing a 45° inclined sawcut, at temperatures of 77 ≤ T ≤ 115 K and confining pressures 0.1 ≤ P ≤ 250 MPa, reveals the frictional laws τ = 0.20 σn + 8.3 MPa for P ≥ 10 MPa and τ = 0.55 σn + 1.0 MPa for P ≤ 5 MPa, where τ and σn are the shear and normal stresses on the
Authors
M. L. Beeman, W. B. Durham, Stephen H. Kirby
Recording strong motion studies
Instruments now permit strong‐motion signals to be recorded over broader band widths, with wider dynamic range and signal resolution and with better data accessibility via computer. These advantages are utilized by the General Earthquake Observation System (GEOS) developed by the United States Geological Survey, by which a microcomputer‐controlled system provides improved strong‐motion data sets,
Authors
Roger D. Borcherdt
Data report for 1980-1981 seismic-refraction profiles in the western Mojave Desert, California
During 1980 and 1981, the U.S. Geological Survey collected seismic refraction data in the western Mojave Desert (fig. 1). The seismic refraction data extends from north of the Garlock Fault, south through the Mojave Desert, and across the San Andreas Fault into the San Gabriel Mountains. This report describes and documents the recorded data, which was collected over three field sessions. In total
Authors
Reid N. Harris, A. W. Walter, Gary S. Fuis
Geologic and hydrologic investigations of a potential nuclear waste disposal site at Yucca Mountain, southern Nevada
Crustal velocity sections based on two seismic-refraction profiles are presented for the area west of Yucca Mountain, Nye County, Nevada. The Crater Flat profile is interpreted in terms of six velocity layers ranging from 1.5 to 6.1 km/s. Interpretation of the Beatty profile reveals an escarpment near the northeast edge of Bare Mountain, where Paleozoic rocks are probably down-faulted 2600 m into
Report on recommended list of structures for seismic instrumentation in the Boston Region
No abstract available.
Authors
Mehmet Çelebi
Report on recommended list of structures for seismic instrumentation in Alaska
No abstract available.
Authors
Mehmet Çelebi
Crustal structure of east central Oregon: Relation between Newberry Volcano and regional crustal structure
A 180-km-long seismic refraction transect from the eastern High Cascades, across Newberry Volcano, to the eastern High Lava Plains is used to investigate the subvolcanic crustal and upper mantle velocity structure there. Near-surface volcanic flows and sedimentary debris (1.6-4.7 km/s), ranging from 3 to 5 km in thickness, overlie subvolcanic Basin and Range structures. East and west of Newberry V
Authors
R. D. Catchings, Walter D. Mooney
Effect of crustal layering upon dislocation modeling
Slip distribution at depth on a fault may be inferred from the deformation observed on the surface. In inverting the surface deformation data to obtain the slip distribution, the Earth is generally approximated by an elastic half‐space. Slip distributions inferred from a half‐space model may contain artifacts, including zones of reversed slip, due solely to effects of layering in the real Earth. T
Authors
James C. Savage