Abstract:
Seismic attenuation may indicate the fluid saturation of a fractured reservoir. However, an important issue for the exploration geophysics is to determine the fracture connectivity from seismic data, because the large-scale fracture clusters support fluid flows. In this paper, we present an algorithm for the statistical modeling of connected fracture systems. The algorithm is based on the discrete fracture network method in combination with the simulated annealing method. Based on the numerical simulation of wave propagation in fractured-porous media, we show that an increase of fracture connectivity leads to an increase of fracture-to-background wave-induced fluid flows; as a result, an increase of seismic attenuation is observed. However, the fracture-to-fracture flows are local and dependent only on the sizes of individual fractures and, hence, cannot be used as a reliable criterion for estimating the fracture connectivity.