Regional Wave Propagation Characteristics in the Middle East and Southern Asia,
Abstract
The regional seismic waves Pn, Sn and Lg were used to map lateral variations of attenuation in the crust and upper mantle. Propagation efficiencies of Sn and Lg were qualitatively analyzed by ranking their amplitudes relative to the P-wave coda. Efficient Sn propagation is observed in the Tien Shan, Tarim Platform, southern Tibet, Yangzi Paraplatform and Sino-Korean Platform. We have confirmed previous studies by finding a lack of Sn transmission in north central Tibet, the Ryukyu and Japan Arcs, Burma and the Baikal Rift. An important observation, which has not been previously reported, is that Sn does not propagate across Mongolia. The elimination of Sn and recent volcanism in north central Tibet and Mongolia suggest that there is partial melt in the upper most mantle beneath those regions. High frequency Lg waves propagate efficiency for most of China, Indochina and Mongolia. Lg signals are attenuated within central Tibet as well as along its southern boundary.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1996
- Accession Number
- ADA325890
Entities
People
- James Ni
- Richard Rapine
- Tom Hearn
Organizations
- New Mexico State University