Study On The Interpretation Method Of Russian Through Casing Resistivity Logging Data

The TCR is an effective means in evaluating remainding oil saturation, and oil saturalion variation with deep investigation depth, the small effects of wellbore, casing and formation heterogeneity, and working at the low-porosity & low-salinity formation. TCR is mainly applied in the qualitative interpretation, and little in quantitative interpretation.Therefore, it is important to establish a quantitative interpretation nethod, and develop a quantitative interpretation software of TCR in evaluat remaining oil,finding out potential oil formation.The measurement principle, operation and feature ofЭКОС31-7 device of Geophysical Exploration Co. of Russia are analyzed. The difference between method of measurement, device structure, and effect factor of Russian TCR and those of Schlumberger TCR is compared. Seven shale content indicators, four methods for porosity are given. Based on the parallel conductance between laminated shale and dispersed shaly sand, and conduction theory for three-dimensional periodic array of charged spheres immersed in an electrolyte, a new generalized double layer conductivity model is proposed for laminated and dispersed shaly sand interpretation, the applicability and commonality of the model is evaluated by using 2 group experiment data of dispersed shaly sand and 1 group measure data of manmade shaly sand sample with variation of dispersed clay content and laminated shale content. And bisection iteration algorithm is used to compute water saturation from the model. a quantitative interpretation software for TCR is developed on Forward, and log data of five wells including la9-jianPS2604 etal are interpreted. The results show that the quantitative interpretation method for the Russian Through Casing Resistivity Logging can determine water-flooded level, detect variation of remainding oil saturation, and find out potential oil formation.