Seismic Tomography Of Pg And Sg/lg And Its Use For Average Upper Crust Structure In Eurasia
- Los Alamos National Laboratory
- MSU
Tomographic inversion oftravel times from first arriving compressional and shear waves for velocity structure has been applied with great success at all length scales, ranging from the laboratory bench-top to the entire Earth. Inversion of later arriving phases has seen a much more limited application. In this paper we present inversion results for regional Pg and Sg for the Eurasian continent to explore its use for understanding average upper crustal velocity structure. Inversion is performed using a damped, smoothed LSQR implementation that solves for site and event terms as well as for velocity along great circle paths between the source and receiver. Results are broadly consistent with published upper crustal velocities for the region. A spotcomparison of Vp/Vs from local and regional studies also compares well with the ratio of observed Pg to Sg velocities from our study where resolution is high. Resolution is determined through the use of checkerboard tests, and these suggest that in regions where data density is high we can resolve features down to at least 2 deg, with 4 deg possible over broader areas. RMS residual reductions are on the order of25% for Sg and 30% for Pg.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC52-06NA25396
- OSTI ID:
- 957786
- Report Number(s):
- LA-UR-08-04628; LA-UR-08-4628; BSSAAP; TRN: US201016%%186
- Journal Information:
- Bulletin of the Seismological Society of America, Journal Name: Bulletin of the Seismological Society of America; ISSN 0037-1106
- Country of Publication:
- United States
- Language:
- English
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