Potential And Distribution Of Oil And Gas Resources In Dongpu Sag

The Dongpu sag experienced three resource evaluations,has entered a mature stage of high exploration,level of exploration is more and more difficult.The resource evaluation results of existing oil and gas and the oil and gas reserves which discovered during exploration are highlighted.It is urgent to re-evaluate the oil and gas resources in Dongpu sag to recognize the potential of the oil and gas resources in the area accurately,and guide the direction of exploration.This article uses two resource evaluation methods,reservoir threshold theory and scale sequence method,respectively.According to the normalized fluid potential theory,the Dongpu sag is divided into 8 reservoir systems,and calculate the amount of depleted hydrocarbons in each reservoir system,then determine the reservoir threshold.Finally,according to the difference between hydrocarbon generation and accumulation threshold,obtain the largest amount of resource in Dongpu sag,is of 63.9×10~8t,the remaining resource is of 57.97×10~8t.Most of the resources are mainly concentrated in reservoir systemⅥandⅦ.There are also part of the amount of resources in the reservoir systemsⅠ、ⅡandⅢ.In the scale-series method,the total proven reserves and remaining resource potential of the Dongpu sag are predicted using the reservoir type as the sequence and the hydrocarbon accumulation system as the unit.As different reservoir types for the evaluation unit,predicted that the total proved reserves of Dongpu sag is of 8.53×10~8t,and remaining proved reserves is of 2.6×10~8t.The fault block reservoirs have the greatest potential,followed by the anticline reservoirs.As petroleum accumulation system for the evaluation unit,predicted that the total proved reserves of Dongpu sag is of 8.19×10~8t,remaining proved reserves is of 2.26×10~8t,mainly concentrated in reservoir systemⅥ.