Hydrocarbon accumulation characteristics of Mesozoic basic volcanic rocks in Dawa area of Liaohe oilfield

The formation and distribution of Mesozoic basic volcanic rocks in Dawa area of Liaohe oilfield are controlled by the tectonic background and fracture system, which presents the distribution characteristics of thick in north and thin in south. For the first time, it is considered that the basaltic volcanic breccia of the underwater eruption type is a good quality reservoir of basic volcanic rock, and its distribution is characterized by pinch-out in the north, phase transition from the south to the east, and east-west nose distribution. There are tectonic-lithologic complex oil and gas reservoirs in this area, and there is ‘relay' three-dimensional transmission system of fault-unconformity surface, forming a reservoir formation model of overall oil bearing,three-dimensional accumulation, hydrocarbon accumulation is controlled by structure and effective reservoir,which provides a basis for further exploration of basic volcanic rock oil and gas reservoirs in Liaohe oilfield.