Attenuation in the Western Great Basin
Abstract
Teleseismic P-wave residuals reveal that beneath the FAULTLESS shot point there is a much smaller high speed anomaly than the observed beneath Pahute Mesa. Ray tracing through the proposed mantle structures in each area result in a shadow zone for European stations for Pahute Mesa shots and little to no effect on energy from FAULTLESS. This suggests that magnitude versus yield curves based on Pahute Mesa explosions are biased, and that the FAULTLESS magnitude versus yield anomaly is a consequence of using those curves. Low frequency estimates of seismic moment of Mammoth Lakes, CA events based on regional surface wave recordings are similar to those using local body wave recordings of the same events. The lack of peaked spectra eliminates one of the proposed dike injection mechanisms. The spectra show no features that suggest mechanisms different from those of 'tectonic' earthquakes. Mammoth Lakes earthquakes discriminate from Nevada Test Site explosions when comparing m sub b and M sub s. Observations of peak Wood-Anderson response along travel paths in the Great Basin indicate greater attenuation at regional distances than in southern California by abut 0.3 M sub L units. Near source M sub L estimates are higher that predicted by Richter's attenuation curve, probably due to the poor near source constraint on the curve.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 15, 1985
- Accession Number
- ADA227790
Entities
People
- Keith Priestly