BISQ model based on a Kelvin-Voigt viscoelastic frame in a partially saturated porous medium*
Nie Jian-Xin1, Ba Jing2, Yang Ding-Hui3, Yan Xin-Fei2, Yuan Zhen-Yu4, and Qiao Hai-Peng1
1. State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
2. Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100084, China.
3. Department of Mathematical Sciences, Tsinghua University, Beijing 100084, China.
4. School of Geosciences, China University of Petroleum, Qingdao 266555, China.
Abstract：
Taking into account three important porous media mechanisms during wave propagation (the Biot-flow, squirt-flow, and solid-skeleton viscoelastic mechanisms), we introduce water saturation into the dynamic governing equations of wave propagation by analyzing the effective medium theory and then providing a viscoelastic Biot/squirt (BISQ) model which can analyze the wave propagation problems in a partially viscous pore fluid saturated porous media. In this model, the effects of pore fluid distribution patterns on the effective bulk modulus at different frequencies are considered. Then we derive the wave dynamic equations in the time-space domain. The phase velocity and the attenuation coeffi cient equations of the viscoelatic BISQ model in the frequency-wavenumber domain are deduced through a set of plane harmonic solution assumptions. Finally, by means of numerical simulations, we investigate the effects of water saturation, permeability, and frequency on compressional wave velocity and attenuation. Based on tight sandstone and carbonate experimental observed data, the compressional wave velocities of partially saturated reservoir rocks are calculated. The compressional wave velocity in carbonate reservoirs is more sensitive to gas saturation than in sandstone reservoirs.
NIE Jian-Xin,BA Jing,YANG Ding-Hui et al. BISQ model based on a Kelvin-Voigt viscoelastic frame in a partially saturated porous medium*[J]. APPLIED GEOPHYSICS, 2012, 9(2): 213-222.
2012, Vol. 9 
