A new approach to interpreting relationship between Rock-Eval S2 and TOC data for source rock evaluation based on regression analyses

Abstract

To evaluate the relationship between total organic carbon (TOC) and Rock-Eval S2 (petroleum potential) of petroleum source rocks, a<br />total of 180 outcrop samples from the black organic matter–rich facies of Mesozoic strata from a locality of southwest of Iran were<br />investigated using Rock-Eval VI pyrolysis and Leco Carbon Analyzer. The linear regression is applied to determine the correlation<br />between Leco TOC and Rock-Eval S1 and S2. The accuracy of the proposed model by this method has approximately 95% conformity<br />according to the Rock-Eval S2 and Leco TOC data (TOC = 0.492 + 0.174 S2). Then, by using the P value method, it was determined<br />that TOC is a function of S2 and S1 only causes the fluctuations. By means of sensitivity analysis of TOC with respect to S1 and S2, it<br />was shown that TOC has a linear relationship with S2 and does not have any noticeable correspondence to S1. The result of this study<br />can be used to evaluate petroleum potential (S2) of organic matter–rich facies by using TOC obtained by Leco Carbon Analyzer. For<br />the studied samples from the organic matter-rich facies, organic carbon richness is a quality and quantity index of petroleum potential.