Abstract：Hydraulic fracturing zones have anisotropic characteristics on the whole.It is necessary to analyze the influence of anisotropic parameters on the focal mechanism and the moment tensor.This paper studies shear-tensile focal mechanism and seismic moment tensor when the source is located in anisotropic media,analyzes the influence of the focal anisotropy on double couple (DC) components,compensated linear vector dipole (CLVD) components,and isotropic (ISO) component.The seismic response characteristics of dry and saturated orthorhombic anisotropy media is also analyzed.Effects of crack parameters and fluid parameters on seismic response are discussed.The following understandings are obtained based on our research:A.The moment tensor in the anisotropic media can be obtained by anisotropic parameters and source quantity; B.The non-DC components caused by shear rupture in anisotropic media depend on the type and intensity of the anisotropy and the direction of the fault plane.High ISO components appear in dry crack media and high CLVD components in water saturation media; C.The far field P wave radiation patterns are different between isotropic and anisotropic media,source characteristics and media anisotropy have significant effects on seismic wave traveltime,amplitude,and polarity.
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