Modeling the Combined Effects of Deterministic and Statistical Structure for Optimization of Regional Monitoring
Abstract
The differences between earthquakes and explosions are largest in the highest recordable frequency band. In this band, scattering of elastic energy by small-scale heterogeneity (less than a wavelength) can equilibrate energy on components of motion and stabilize the behavior of the Lg wave trapped in the Earth's crust. Larger-scale deterministic structure (greater than a wavelength) can still assume major control over the efficiency or blockage of the Lg and other regional/local seismic waves. This project models the combined effects of the large-scale (deterministic) and the small scale (statistical) structure to invert for improved structural models and to evaluate the performance of yield estimators and discriminants in the region of the Lop Nor test site. This is accomplished by synthesizing seismograms using a radiative transport technique to predict the high frequency coda (2 to 4 Hz) of regional seismic phases at stations having known large-scale threedimensional structure, combined with experiments to estimate the effects of multiple-scattering from unknown small-scale structure. We describe a code to shoot body wave rays through general deterministic 3-D structure, including the coda envelope sensitivities to parameters describing the heterogeneity spectrum, intrinsic attenuation, Moho transition, and tectonic release of nuclear tests. We predict that discriminants in this region based on P/Lg amplitude ratios will best separate earthquake and explosion populations at frequencies 2 Hz and higher.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 2015
- Accession Number
- ADA624469
Entities
People
- Christopher J. Sanborn
- Michele Fitzpatrick
- Nil Mistry
- Steven Walsh
- Vernon F. Cormier
Organizations
- University of Connecticut