The underground medium is affected by multi-stage tectonic movement,the phenomenon that the crack exists in multiple groups is common,and the connectivity between multiple sets of fractures will affect the elastic parameters of the medium.When the elastic modulus of a saturated rock with two sets of staggered fractures are calculated,in the case where the fracture is connected,the elastic parameters of the dry rock are calculated first,and then the elastic parameters of the fluid-containing fracture medium are obtained by anisotropic fluid replacement.In the case of non-intersecting fractures,first the saturated crack toughness is calculated for the two sets of fractures,and then the overall elastic parameters of the saturated fractured rock are calculated.Some conclusions have been reached:①Under oil-water saturation conditions,when the fractures are connected,the shear-wave splitting parameters change less with the increase of oil saturation;when the fracture is not connected,the shear wave splitting parameter changes greatly with the increase of oil saturation.②As the crack inclination angle θ increases,the shear wave splitting parameter decreases.③Under oil saturation conditions,shear wave splitting parameters increase slightly with increasing porosity when the fractures are connected;when the fracture is not connected,the shear wave splitting parameter decreases with the increase of porosity,and the degree of reduction is relatively large.
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