Abstract Up to now, the primary method for studying critical porosity and porous media are experimental measurements and data analysis. There are few references on how to numerically calculate porosity at the critical point, pore fluid-related parameters, or framework-related parameters. So in this article, we provide a method for calculating these elastic parameters and use this method to analyze gas-bearing samples. We first derive three linear equations for numerical calculations. They are the equation of density ρ versus porosity φ, density times the square of compressional wave velocity ρVP2 versus porosity, and density times the square of shear wave velocity ρVS2 versus porosity. Here porosity is viewed as an independent variable and the other parameters are dependent variables. We elaborate on the calculation steps and provide some notes. Then we use our method to analyze gas-bearing sandstone samples. In the calculations, density and P- and S-velocities are input data and we calculate eleven relative parameters for porous fluid, framework, and critical point. In the end, by comparing our results with experiment measurements, we prove the viability of the method.
The research is supported by the National Natural Science Foundation of China (Grant No. 40874052) and the Key Laboratory of Geo-detection (China University of Geosciences, Beijing), Ministry of Education.
Cite this article:
NIU Bin-Hua,SUN Chun-Yan,YAN Guo-Ying et al. Linear numerical calculation method for obtaining critical point, pore fluid, and framework parameters of gas-bearing media[J]. APPLIED GEOPHYSICS, 2009, 6(4): 319-326.
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