HR: 0830h
AN: S11D-0326    [PDF]
TI: Preliminary Assessment of Basin-Induced Amplification of Weak Ground Motion in Pahrump Valley, Nevada-California
AU: * Abbott, R E
EM: reabbot@sandia.gov
AF: Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185-1168 United States
AB: Sedimentary basins can increase the magnitude and extend the duration of seismic shaking. This potential is investigated for Pahrump Valley, Nevada-California, by comparing the waveforms and spectra of weak ground motion recorded in the city of Pahrump, Nevada, to those recorded in the nearby mountains. Preliminary results, based upon a few events, suggest significant amplification (5x or more relative to a rock site) at frequencies ranging from 4 to 15 Hz, depending on the location of the basin station. The Pahrump Valley is located approximately 50 km WNW of Las Vegas. Gravity data suggest that the city of Pahrump sits atop a narrow, approximately 5 km deep sub-basin in the valley. The city of Pahrump has seen tremendous growth in recent years (over 200% population increase in 10 years) and the growth rate is increasing. Several nearby fault systems represent a seismic hazard to the population of Pahrump and its neighboring communities; the most notable hazard is from the Pahrump Valley Fault Zone which runs along the western edge of Pahrump Valley. Proximity to the more active Death Valley and Furnace Creek Fault Zones, both less than 50 km distant, and possible future underground nuclear tests at the Nevada Test Site, 75 km to the north, also represent a potential hazard.
DE: 7212 Earthquake ground motions and engineering
DE: 7223 Seismic hazard assessment and prediction
SC: Seismology [S]
MN: 2003 Fall Meeting