Electrical Struture of the Crust in Manas Earthquake Area,Xinjiang,China

Magnetotelluric sounding data obtained recently in Manas earthquake area were processed. In the result, curves of apparent resistivity, impedance phase, skewness and optimum rotation angle versus period and the real magnetic induction vectors were obtained. Then the data of all measuring points were interpreted by 2D automatic inversion. The result indicates that along the sounding profile the shallow crust can be divided into 5 segments and the deep crust can be divided into 3 segments, with faults or deep-seated fault zones as the contact boundaries between them. The sedimentary cover along the profile extents down to depth about 12 km in maximum and a low-resistivity body exists in the crust in southern section of the profile. The interpretation results are well consistent with geological and other geophysical data. The Manas M7. 7 earthquake occurred near a contact zone where the electrical structure of the crust sharply changes.