Analysis of velocity model for the Tien-Shan lithosphere and the double-difference method for hypocenters location using seismic network KNET data
Category: 13-2
UDC 550.34.012
N.A. Sycheva, S.I. Kuzikov
Research station of RAS in Bishkek city, Kyrgyzstan
Abstract
The comparative analysis of four most known lithospheric velocity models for territory of Central Tien Shan is carried out. For accuracy of calculation of the hypocenters on study region the most preferable are Steve Roecker's model and model of Institute of dynamics of geospheres of the RAS. However the model of T.P. Grin describes a crust velocity structure within perimeter of seismological stations of KNET more adequately and allows receiving the hypocenters of local events with the minimum values of errors. The catalogue for more than 4500 seismological events according to network KNET for 1994–2008 with the relocated hypocenters by the double-difference algorithm was calculated; also the catalogue with the corrected hypocenters for ~3500 events is received. Average relocation of the hypocenters on a longitude and latitude are ~1.1 km, on depth are 5.1 km, thus errors of calculation of parameters of earthquakes have on the average decreased in 1.5–2 time.
Keywords: earthquake, hypocenter, velocity model of the lithosphere, Double-difference method.
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