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S.L. Hanson

Publications and source records attributed to S.L. Hanson.

7 recordsLinked to original sources
USGS1993

Pilot studies of seismic hazard and risk in North Sulawesi Province, Indonesia

Earthquake ground motions in North Sulawesi on soft soil that have a 90% probability of not been exceeded in 560 years are estimated to be 0.63 g (63% of the acceleration of gravity) at Palu, 0.31 g at Gorontalo, and 0.27 g at Manado. Estimated ground motions for rock conditions for the same probability level and exposure time are 56% of those for soft soil. The hazard estimates are obtained from seismic sources that model the earthquake potential to a depth of 100 km beneath northern and central Sulawesi and include the Palu fault zone of western Sulawesi, the North Sulawesi subduction zone, and the southern most segment of the Sangihe subduction zone beneath the Molucca Sea. An attenuation relation based on Japanese strong-motion data and considered appropriate for subduction environments of the western Pacific was used in determination of ground motions. Following the 18 April 1990 North Sulawesi earthquake (Ms 7.3) a seismic hazard and risk assessment was carried out. -from Authors

Earthquake Spectra↗
USGS1990

Probabilistic earthquake acceleration and velocity maps for the United States and Puerto Rico

The ground-motion maps presented here (maps A-D) show the expected seismic induced or earthquake caused maximum horizontal acceleration and velocity in rock in the contiguous United States, Alaska, Hawaii, and Puerto Rico. There is a 90 percent probability that the maximum horizontal acceleration and velocity shown on the maps will not be exceeded in the time periods of 50 and 250 years (average return period for the expected ground motion of 474 and 2,372 years). Rock is taken here to mean material having a shear-wave velocity of between 0.75 and 0.90 kilometers per second. (Algermissen and Perkins, 1976).

Miscellaneous Field Studies Map↗
USGS1982

Probabilistic estimates of maximum acceleration and velocity in rock in the contiguous United States

Maximum horizontal accelerations and velocities caused by earthquakes are mapped for exposure times of 10, 50 and 250 years at the 90-percent probability level of nonexceedance for the contiguous United States. In many areas these new maps differ significantly from the 1976 probabilistic acceleration map by Algermlssen and Perkins because of the increase in detail, resulting from greater emphasis on the geologic basis for seismic source zones. This new emphasis is possible because of extensive data recently acquired on Holocene and Quaternary faulting in the western United States and new interpretations of geologic structures controlling the seismicity pattern in the central and eastern United States.

Open-File Report↗