Propagation Of Elastic Wave In A Fluid-Saturated Porous Media And Attenuation Characteristics Evaluation

Elastic waves in porous media based on the Biot theory are received widespread attention; however, seismic exploration in the coalfield shows few examples of applications. Based on the Biot theory, the impact of isotropic dissipative porous media parameters on the various types of wave phase velocity or attenuation was studied. The results show that the impact of permeability is the very opposite of the impact of viscosity upon attenuation. The effects of decrease in permeability and increase in viscosity are almost identical and vice versa. Under the guidance of the above-mentioned conclusions, the staggered grid finite difference forward and physical simulation forward were respectively used to simulate seismic data, spectral analysis based on the forward seismic data shows that there is significant difference in the spectrum of porous media and single-phase media, showing the spectral characteristics "low-central-frequency value, low-frequency high-value, high-frequency low-value ",these characteristics have been verified under usage of forward data. During time-frequency analysis process, the sampling rate influences the accuracy of spectrum, as well as time-frequency windows, and so on. Gu-gui in the Huainan mining area, Ju-ji in the Yongcheng mining area used P-wave attenuation characteristics to predict the limestone water-rich region; Gu-qiao in the Huainan mining area used the S-wave attenuation characteristics to predict the coal seam gas-rich region.