Seismic Structure of the Caspian Basin and Surrounding Region.
Abstract
The crust and upper mantle structure of the south Caspian Basin and Turkmenian Lowlands is enigmatic. From Soviet deep seismic sounding data collected in the 1960's, the crust appears to consist of two layers: a thick sedimentary section (15-25 km) with a low P-wave velocity (3.5-4.0 km/s) overlying a 12-18 km thick basaltic lower crust. It has been suggested that this basaltic lower crust is 'oceanic-like' crust and that the south Caspian Basin represents a section of relic ocean from a Paleozoic-Triassic ocean or a Mesozoic - Paleogene marginal sea. Improved knowledge of the crust and upper mantle velocity structure of the south Caspian Basin is important in a seismic verification context because of the anomalous effect it has on regional seismic waveforms. To investigate the crust and upper mantle structure of the south Caspian Basin, we have installed six three-component seismograph stations within the former Soviet Republics of Turkemenia and Azerbaijan. Our objective is to determine the velocity structure of this region using both body wave receiver function and surface wave modeling techniques. We present receiver function inversion results for four sites and fundamental mode Rayleigh wave observations for two great circle paths across this region.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1996
- Accession Number
- ADA326187
Entities
People
- Michail Rozhkov