Analysis of 3d complex structure and heterogeneity effects on formation and propagation of regional phases in Eurasia. Final report, 15 August 1992-30 September 1994

Technical Report · Tue Dec 13 04:00:00 EST 1994

OSTI ID:103990

Lay, T; Wu, R S

This document is the final report for this grant to develop new three-dimensional wave propagation techniques for high frequency waves in heterogeneous media. The report is divided into four sections, each being a published paper sponsored by this grant. In the first section we formulate a one-way wide-angle elastic wave propagation method for arbitrarily heterogeneous media in both the space and wavenumber domains using elastic Rayleigh integrals and local elastic Born scattering theory. In the second section this complex phase screen method is compared with fourth-order finite differences and exact eigenfunction expansion calculations for two-dimensional inhomogeneous media to assess the accuracy of the one-way propagation algorithm. In the third section, an observational study of continental margin structure influence on Lg propagation is presented, using data from the former Soviet stations for nuclear explosions at Novaya Zemlya. We find that bathymetric features can be correlated with energy levels of Lg, suggesting that waveguide structure influences regional phase energy partitioning. This idea is pursued in the fourth section, using Eurasian earthquake and nuclear explosion data along with information about the crustal structure in Eurasia. We develop empirical relations that reduce the scatter in the P/Lg discriminant at low frequency.

• Research Organization: California Univ., Santa Cruz, CA (United States). Inst. of Tectonics
• OSTI ID: 103990
• Report Number(s): AD-A--291214/5/XAB; CNN: Contract F49620-92-J-0461
• Country of Publication: United States
• Language: English

Related Subjects

35 ARMS CONTROL
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
ARMS CONTROL
EARTHQUAKES
NUCLEAR EXPLOSIONS
PROGRESS REPORT
REGIONAL ANALYSIS
SEISMIC WAVES