Effects of Finite Fracture Thicknaess on Seismic Dispersion and Attenuation in Saturated Rocks with Aligned Penny-Shaped Cracks: Theory versus Numerical Simulation

摘要

Seismic dispersion and attenuation are important attributes for the detection and characterization of saturated fractured formations. An important mechanism for this is the wave-induced fluid flow (WIFF) between the fractures and the host rock. While many theoretical models have been proposed to describe this mechanism, most of them have the assumptions of infinitesimal fracture thickness and dilute fracture concentration. Hence, in this work, we extend the model for the rocks with aligned penny-shaped cracks by considering the effect of finite fracture thickness and then test its validity by comparing with the numerical simulations. The results show good agreement between the theoretical prediction and the numerical simulations even under the relatively high fracture density. Furthermore, it is shown that the finite fracture thickness effect is small at low frequencies but significant at high frequencies.