Seismic Response of Fractures with Different Porosities and Viscosities

A finite-difference wave equation method is developed to model wave propagation in anisotropic media, in order to observe the effects of fractures on seismic response. As the elastic constants of anisotropic media that represent fractures are frequency dependent, wave simulation is implemented in the frequency domain. Diffractions due to scattering of fractures are constructed for investigating seismic response of fractures with different porosities and viscosities. Among these two parameters, the variation of porosity variation causes stronger response than viscosity variation does. These relative sensitivities may be considered quantitatively in a simultaneous inversion for these parameters in the future. Meanwhile, the position of a fracture gallery can be clearly identified from strong, fanlike energy mass at the high frequency of the diffraction spectrum.