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 equilibriate 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 at selected IMS monitoring stations in Eurasia. This is accomplished by synthesizing seismograms using a radiative transport technique to predict the high frequency coda (>5 Hz) of regional seismic phases at stations having known large-scale three-dimensional structure, combined with experiments to estimate the effects of multiple-scattering from unknown small-scale structure. We describe a code and preliminary tests to shoot body wave rays through general deterministic 3-D structure, including the computation of quantities required to synthesize high frequency body wave coda generated by small-scale, statistically described heterogeneity. Modifications in this period include 3-D interfaces with generalized dips and generalized 3-D reflection-transmission at the interfaces. Example regional waveform envelopes at 4 Hz are synthesized and discussed for an earthquake and explosion source in the Lop Nor region.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 2014
- Accession Number
- AD1001042
Entities
People
- Christopher J. Sanborn
- Michele Fitzpatrick
- Nil Mistry
- Steven Walsh
- Vernon F. Cormier
Organizations
- University of Connecticut