Porosity cut-off values evaluated by classifying reservoir rock types from cores data. A case study for Triassic reservoir T1, Blocks 433a&416b, Algeria

Abstract

This paper introduces the method to determine the porosity cut-off values by classifying rock types from cores data based on permeability cut-off value by 1 mD (for sandstone reservoir with oil). The purpose of this method is to calculate net pay reservoir more precisely for estimating hydrocarbons initially in place and building static models. Normally, the cut-off values of porosity are defined on a cross-plot of porosity versus permeability obtained from core data. However, the results of petrophysical analysis are not consistent with DST results. There are some wells with reservoir net pay of several meters, but the DST does not deliver flows. The application of a new method determining the porosity cut-off values on T1 reservoir shows the reservoir net pay is consistent with actual data of the field.