Regional Studies with Broadband Data.
Abstract
A laterally averaged one dimensional P and S wave velocity structure is obtained for Silent Canyon Caldera, located beneath Pahute Mesa at the Nevada Test Site. The velocity models are derived from a linearized damped least squares travel time inversion for slowness gradient perturbations. A total of 72 P wave and 20 S wave travel times generated from 13 different explosions, and obtained at scattered locations above the caldera, are used in the inversion. The structure is modeled using linear velocity gradients. The inversion produces a model which increases in velocity from 1.50 km/sec at the surface to 2.35 km/sec at 2.5 km depth for S waves. The P and S wave models produce travel time residuals which are typically less than 0.1 and 0.2 seconds, respectively, which is within observational error. However, P wave amplitude ratios and waveform characteristics of data collected from 7 explosions buried near 625 m depth indicate the presence of lateral variations within the caldera which may be significant to nuclear source studies. Keywords: Seismic waves, Seismic data, Nuclear explosion, Velocity structure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 06, 1986
- Accession Number
- ADA172317
Entities
People
- Lane R. Johnson
- Thomas V. McEvilly
Organizations
- University of California, Berkeley