Abstract: The Erlian basin is a large Meso-Cenozoic sedimentary basin in northeastern China, with more than 40 depressions of varying sizes. Their genesis were closely related to the fossil steep blocks produced by regional faulting. These blocks not only controlled the different lithofacies zones, the centers of subsidence and the source rocks, but also formed, during the many stages of tectonism, many different structural zones and types of traps, keeping the distribution of oil and gas accumulation under their direct control. This may serve as a clue to the discovery of a new oil region for setting up a new oil base.