Gold enrichment mechanism in crude oils and source rocks in Jiyang Depression

Gold enrichment in Crude oils and source rock samples has been reported in Jiyang Depression, Shengli Oilfield. In order to study the mechanism of gold enrichment, 18 samples collected around deep faults were analyzed by geochemical methods. The results indicate that the gold accumulation in Jiyang Depression is closely related to the mantle fluids and sulfur polycyclic aromatic hydrocarbon (S-PAH) in oil and source rocks. Gold elements could be from the mantle fluids and accumulated when they were carried into Source rocks, especially when they encountered S-PAH Rare earth element (REE) contents are high when gold contents are high. This phenomenon may indicate that a part of REE is also from the mantle fluids.