Distribution of local earthquakes in the crust beneath central Lake Baikal
V.D. Suvorova, Ts.A. Tubanovb
a Institute of Petroleum Geology and Geophysics, Siberian Branch of the RAS, 3 prosp. Akad. Koptyuga, Novosibirsk, 630090, Russia
b Geological Institute, Siberian Branch of the RAS, 6a ul. Sakhyanovoi, Ulan-Ude, 670047, Russia
Keywords: hypocenter location; crust; Baikal rift
Pages: 611-620
Abstract
We have located earthquake hypocenters in the area of central Lake Baikal using the Hypoellipse inversion of direct P traveltimes collected by a local seismological network of seven stations in 2001 through 2005. The location accuracy depends on the agreement between the reference velocity model and the real subsurface. Traveltime residuals have no bearing on the accuracy of depth estimates due to origin time errors.
Hypocenter location with reference to a DSS-derived layered velocity model predicts that the crust is seismogenic between 10 and 22 km. The hypocenters cluster densely in belts trending in NE and SE directions along and across Lake Baikal. Earthquakes become deeper from 10 to 22 km toward the Selenga basin.
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