The Analysis Of The Anisotropic Seismic Forward Modeling For Hydraulic-fractured Shale

Shale gas is the center of the unconventional oil and gas research all over the word.It has the low porosity and low permeability.The hydraulic fracturing is an important tool to develop the shale reservoirs.Because the hydraulic fracture is a good guide path to enhance the shale gas production.The distribution of the hydraulic fracture has a significant effect on the hydraulic fracturing.On the other hand,being clear on the hydraulic fracture how to influence the anisotropy of the medium has pratical significance.This paper first calculates the fracture compliances by simulating 3D hydraulic fracturing process.And then the elastic parameter of the fractured media is estimated using the equivalent orthorhombic medium theory.Baesd on the above work,we build the seismic forward model and according to the seismic data to analyze the anisotropyThe numerical results show that hydraulic fracturing can generate weak azimuthal anisotropy.When the shale is fractured,the equivalent medium is an orthorhombic medium and the velocity decreases.And with the fracture developing better,the elastic parameters are getting smaller.The shear wave is more sensitive to the hydraulic fracture than the P-wave.