Sequence patterns for the marine strata in potential oil and gas pools in the central Yangtze area

The present paper discusses the sedimentary-tectonic settings of oil and gas accumulation in marine strata, sequence patterns for the marine strata and areas prospective for oil and gas pools in the central Yangtze area. Such an area should be well made up of source rocks, hydrocarbon reservoirs and seals. More precisely, the source rocks of the transgressive systems tract within the H-type second-order sequence framework consist of more T-type and/or less H-type third-order sequences, whereas the hydrocarbon reservoirs of the highstand systems tract within the H-type second-order sequence framework are composed of more H-type and/or less T-type third-order sequences. The potential areas in the Lower Palaeozoic strata include western Hunan and Hubei, Yichang slope, and southern Jianghan Plain, and those in the Upper Palaeozoic strata involve eastern Chongqing, western Hubei and Jianghan Plain.