Quantification and implications of two types of soluble organic matter from brackish to saline lake source rocks

Two types of soluble organic matter, the free and adsorbed, were obtained and quantified from the brackish to saline lake source rocks. The adsorbed type was extracted with chloroform, solvent mixtures of methanol：acetone：chloroform （MAC） and CS2：N-methyl-2-pyrrolidinone （CSz/NMP）. The total amounts of the two types of soluble organic matter from some immature source rocks are 〉830 mg/g TOC, more than 63% of the total organic matter in these samples. This result indicates that the majority of the organic matter in the immature source rocks in the brackish to saline lake basin is soluble, and is significant for study of petroleum formation and helpful for petroleum exploration in the brackish to saline lake basin.