Comparison of Fracture Models for Seismic Wave Propagation in a Medium with Multiple Parallel Fractures

Rock fractures create a secondary porosity giving new fluid paths due to the increased permeability. Seismic waveforms can provide useful information on the fracture network of a rock as a result of wave interaction with the fractures. This study is targeted at improving the understanding of wave propagation modelling in fractured media. For this purpose we use numerical modelling to model wave propagation through multiple parallel fractures based on an experiment with ‘simulated’ fractures in a steel block from (Pyrak-Nolte et al. 1990). Three models (Transversely Isotropic, Heterogeneous Transversely Isotropic and explicit fracture representation), each one using a different solution to the wave propagation in fractured medium, are developed in order to compare the similarities and differences. We use a P- and S-wave source which we have inverted from the experiment to study propagation in two different orientations perpendicular and parallel, to the fractures.