The Role of Soluble Organic Matter in Shale Oil “Sweet Spots” Prediction: An Investigation of Shale With Different Lithofacies in the Dongying Sag

Lithofacies are the fundamental geological units for shale oil and gas exploration development, soluble organic matter (SOM) is most similar to crude in composition. Both aspects attract our attention interpretation of SOM different lithofacies, which can provide direct evidence predict “sweet spots”. Here, twenty-five samples were collected from Eocene Shahejie Formation Dongying Sag subjected X-ray diffraction, Rock-Eval pyrolysis, characterization. Comparison contents shales with lithofacies revealed remarkable differences: 1) The SOM, saturates total hydrocarbons (THC) showed order detrital massive mudstone < homogenous wide laminated discontinuous fine gypsum-bearing mudstone, content was controlled by through differences both OM minerals. 2) mudstones mainly composed resins. Saturates main component shales. aromatics. saturates, percentage asphaltenes quite high. Based on evaluation parameters high-quality terms abundance (i.e., THC or saturate contents) quality index asphaltene percentage), fine, regarded as relatively favorable lithofacies. combination, Es3x Es4ss (upper section Es4s) interpreted spots” development. Thus, it great significance study characteristics