Study On Study On Main Controlling Factors Of Oil And Gas Accumulation In Shahejie Formation Of Liaohe Xinkai Oilfield

Xinkai Oilfield is located in the north of Bohai Bay Basin and the south of the eastern depression of Liaohe Depression.It is a is a large monoclinal structure which towards the southeast in the region based on the background of the central bulge.The exploration rate of the study area is low,there are large areas to be explored,and the mining degree is low,which requires further detailed study.Based on the comprehensive utilization of core data,well logging data and 3d seismic data,this paper firstly reclassifies and compares the strata,then realizes the tectonic characteristics of the whole region,and adopts the seismic inversion method for reservoir prediction.Then combined with sedimentary facies and reservoir physical properties,distribution and other characteristics,oil and gas accumulation patterns and main control factors are discussed.The main conclusions are as follows:There are many stages of tectonic activity in the eastern depression of Liaohe Depression.The main faults in the study area are Eejiegou fault and Xinkai fault,both of which are northeast-trending and have long length extension,which control the structure and deposition of the whole area.The dominant facies of Shahejie Formation in Xinkai Oilfield are distributary channel and estuarine bar.These two facies belts develop thick reservoirs,while the sand bodies developed in other phase states,such as underwater distributary channel,are relatively thin in thickness,poor in connectivity and low in oil and gas enrichment.The sedimentary facies belt has a high degree of control over reservoir distribution.The study area is the main development of S₁ and S₃ sandstone reservoir,because of the sedimentary environment change,the sedimentary facies change is bigger,complex reservoir sedimentary type.The study area has good hydrocarbon accumulation conditions.The oil source comes from the adjacent oil source depressions,and there are multiple reservoir-cap combinations.At the same time,the study area has complex structural conditions.