Numerical Calculation of Electric and Elastic Properties of Porous Rocks as a Function of Fluid Saturation
Physical properties (i.e.: electric and elastic properties) of porous media are very important and required in many fields, such as geotechnical engineering, petroleum engineering, geophysics, etc. In this study, calculation of electric and elastic properties is conducted by means of finite element method from digital rock images. Porous rock images used in this study consists of generated numerically artificial rock models and real rocks images taken from micro-CT-scan. Random consolidation processes are applied to generate artificial rocks for different porosity. The porous media is then saturated by fluid and physical properties are calculated at each degree of fluid saturation. Influence of fluid saturation degree on electric and elastic properties of both porous media is analyzed. The results show that fluid saturation changes electric and elastic properties of rocks. Fluid conductivity has quite significant influence on the resistivity. Electrical properties decrease rapidly until 20% of fluid saturation and only slight change for higher saturation. Bulk modulus increases for higher saturation.
KeywordsElectric properties Elastic properties Fluid saturation Finite element method
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