NUMERICAL SIMULATION OF ELECTRO MAGNETIC PROPAGATION LOG

Abstract

the determination of water saturation, when the formation waters become less saline and of fluctuating salinity, and electrical logs do not provide correct information. Electromagnetic wave propagation in a porous medium is controlled by its conductivity and dielectric permittivity (or dielectric constant). The water has a large value of dielectric permittivity, much higher than other fluids or minerals found in reservoir rocks. This contrast makes the dielectric measurements particularly sensitive to the water filling the pore space. Synthetic electromagnetic propagation logs stimulating the response of the log under different conditions of porosity and saturation in a reservoir have been computed. These synthetic logs have been then used to derive the porosity and saturation. Different conditions of porosity and saturation in oil and gas bearing reservoir rocks have been used to generate the synthetic data and its inversion in terms of porosity and saturation. -The inverted values of water saturation show good agreement with original values. The agreement becomes better as water content of the formation increases due to increase in porosity and water saturation.