Petroleum geologic features and exploration targets in Anda region, Songliao Basin

Based on geologic, drilling, seismic and geochemical data, it was analyzed in this paper the tectonic evolution, source rock, sediment, reservoir-cap combination, oil-water relationship as well as accumulation type and characteristics in Anda region. Petroleum geologic features in the region were concluded as follows. Organic matter abundance of source rock is high, favorable for hydrocarbon generation and migration. Physical properties of sandbody reservoir in distributary channel are good, providing room for hydrocarbon accumulation. The favorable combination of reservoir and cap rock helps hydrocarbon accumulation and preservation. Fracture which leads to source rock works as pathway for hydrocarbon migration. Overpressure in mudstone in the 1st member of the Qingshankou Formation drives hydrocarbon to migrate. In the study area, water locates at the bottom and oil locates at the top. Reservoirs are mainly fault-lithology and lithology-tectonic ones. The Fuyu oil layer in the region is controlled by mature source rock, overpressure in the 1st member of the Qingshankou Formation, favorable migration pathway and reserve condition. Further exploration target in the region was pointed out.