Identifing reservoir fluid properties in Daniudi Paleozoic gas field by fuzzy clustering analysis method

The sandstone reservoir in Daniudi Paleozoic gas field in Ordos Basin belongs to low porosity and low permeability reservoirs. It is very difficulty to recognize reservoir fluid properties using well logs. In order to improve the accuracy of the identification of reservoir fluid properties, according to the actual geological conditions of reservoirs, four characteristic parameters of the reservoir fluid properties are extracted. Four parameters are porosity, water saturation, the ratio of formation resistivity and the resistivity calculated by acoustic log. The reservoir fluid properties had been automatically identified by Fuzzy Clustering Analysis (TATAL FUZZY ISODATA-TFI) method. The actual data processing results show that the application effect is better and coincidence rate is more than 85%.