The Guanzhen subsag in northern Jiangsu Basin has different zones and sedimentary systems. The sedimentary systems include meandering stream's delta, shore shallow lake, deep lake, alluvial fan, and subaqueous fan. These systems can form subtle reservoirs between them. The deep lake sedimentary system is in the deep sag zone, while the meandering stream's delta system is in the gentle gradient zone. The integrated patterns of sedimentary systems include subaqueous fan-deep lake-meandering stream's delta and alluvial fan-shore shallow lake-little delta. The formation of a big fan delta may be favored during the sedimentary time of the Dannan system.