Method and Application of Reservoir Unit Division in Continental Faulted Lacustrine Basin: An Example from the L70 Fault Block in Raoyang Sag

[Image: see text] The continental faulted lacustrine basin is an important type of continental oil and gas basin with typical compound oil and gas accumulation characteristics. The traditional petroleum geological theory usually makes a general analysis of multiple reservoirs. It uses the structural model to understand the reservoir and has a vague understanding of the reservoir. The actual exploration is inconsistent with the traditional theory, which restricts exploration and development. In this case, taking the lower submember of Sha 1 of Shahejie Formation of L70 fault block in Raoyang sag as an example, the concept of reservoir unit is put forward, and the reservoir is redivided using the “four diagrams and four steps” method, the oil–water distribution is clarified, the type of reservoir unit is defined, and multiple potential reservoir units are proposed. It enriches and perfects the traditional petroleum geological theory, provides a new research method and idea for petroleum exploration and development, and ushers in new opportunities for the developed old oil fields.