Abstract The saturation analysis date of sealed coring wells can provide the most direct quantitative data for studying remaining oil distribution. However, the oil/water saturation values measured in laboratory test usually deviate form the true values of underground conditions due to multiple factors, and they must be corrected for exact data. Most existing calibration methods consider the changes in pressure and pore conditions during the coring process, ignoring the differences in the oil/water saturation values caused by lithology and electrical properties. In this paper, well J2-6-A145 is selected as the study object. Firstly, the lithology and oil water loss rate are determined as the main influencing factors of oil water saturation by using the Analytic Hierarchy Process. Then a classification statistical correction chart based on lithology and oil-water loss rate is established in sequence, with correlation coefficients ranging from 0.92 to 0.97. Finally, based on the Electrical Property Water Content Relationship Chart of mining production statistics, considered the differences in oil water volatilization under different content levels. The oil-water saturation under different Oiliness is corrected by combining production dynamics chart and permeability curve. A saturation correction method based on statistical regression is obtained by considering multiple factors such as lithology, oil-water loss rate, oiliness, permeability and production dynamics. This method improves correlation after segmented regression, better reflects the oil content of the formation by considering dynamic factors, and provides an accurate data foundation for understanding and evaluating the distribution pattern of remaining oil.
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