Seismic sedimentology of sand-gravel bodies on the steep slope of rift basins — A case study of the Shahejie Formation, Dongying Sag, Eastern China

A variety of genetic types of reservoirs with good hydrocarbon accumulation conditions have been developed in petroliferous rift basins. The near-provenance, coarse-grained depositional system on the steep slopes of rift basins has become an important oil and gas exploration area. However, due to the large changes in lithologies and difficulties in its identification and characterization, the challenges in oil/gas exploration are significant. Seismic sedimentology, in this case, provides an effective means of identifying and characterizing the complex, coarse-grained sediments. In this paper, a large number of cores, log and seismic data are used, the third order and fourth order sequence frameworks are established in the Shahejie Formation on the steep slope of the northern Dongying Sag in eastern China. Three types of lithofacies, including conglomerates, sandstones and mudstones with 12 sub-species facies types have been identified and the relationship between different lithofacies types and deposition...