Characteristics of hydrocarbon migration and accumulation in Weixinan sag of Beibuwan Basin

Weixinan sag in Beibuwan Basin is a faulted lake basin in type.In hydrocarbon migration and accumulation process,the faults can connect the source rocks with reservoirs.The unconformities result in contact and connection between the different formations which provide hydrocarbon lateral migration paths for the adjacent traps to form accumulations.The distribution characteristics of hydrocarbon in Weixinan sag can be described as rift connecting the source rocks,hydrocarbon migrating along the ridge,source rocks from both sides,multiple accumulations in a single structure and oil-bearing in full sag,and formed a hydrocarbon accumulation zone of multiple reservoirs and accumulations with same source.