Application of Geophysical Technologies in Lithostratigraphic Reservoir Exploration within Slope Zones of Qikou Sag

The Qibei slope is located within the Bohai Bay Basin, southwest of the Qikou sag between the Gangxi fault and the South Dagang fault (Figure1). West of the Qibei slope lies the Kongdian bulge, which is an eastward dipping slope structure with long-term development. Subject to different basement subsidence as well as the differential movements of the two major boundary faults, the Qibei slope can be divided into three flexural slope regions; from west to east, they include the: high slope, middle slope and low slope. The sandstones of the Es2 and Es3 Member of the Paleogene were supplied by the trough fault and distributed along the eastward dipping slope. The target layer is at the favorable burial depth and the reservoir property is good, correlating well with the slope break structure and the oil sources. It is a favorable zone for lithologic oil/gas accumulation.