Hydrocarbon Accumulation Laws and Model of MM Oilfield in Bohai Bay Basin

MM Oilfield was located in Bohai Bay Basin, far from the western hydrocarbon source kitchen. The reservoir types in MM Oilfield were mainly lithological-structural reservoirs with small-scale. By studying the structural evolution history of Bohai Bay Basin and fully combining the seismic data, logging data and geology data of MM Oilfield, the hydrocarbon accumulation law of MM oilfield was summarized. That was remote hydrocarbon source and fault shielding accumulation. Reservoir abundance of MM Oilfield was affected by the structural location and the remote source of oil and gas. The distribution of the oil reservoir was influenced by the lateral sealing of the fault. The scale of the oil reservoir was controlled by the size of the trap and the physical conditions of the reservoir. C7 layer of the formation was the main carrier for lateral migration. Faults was the channel for vertical migration of oil and gas. The accumulation model of MM oilfield was jointly determined by the matching relationship between the fault distance, the thickness of the caprock and the trap conditions. Three types of oil reservoirs were mainly developed, namely, broken nose reservoir, lithology-fault reservoir and fault-lithology reservoir.