Study On The Accumulation Model Of The Fourth Member Of The Shahejie Formation In The Niuxintuo Area Of Dongdupo, The Western Sag Of Liaohe

In this paper,the E₂s_4s member of Shahejie Formation in Niuxintuo area,the East steep slope of the western depression of Liaohe is selected as the research area.Based on the well logging data,logging data,seismic data and oil testing data of the oil field,and on the basis of previous studies,combined with their own research,it is considered that the fourth member of Shahejie Formation in Niuxintuo area has two kinds of oil reservoirs:tight deep basin reservoir and tight conventional reservoir.The fourth section of niuxintuosha is divided into three sub sections.According to the theory of hydrocarbon expulsion threshold,the buried depth of hydrocarbon expulsion threshold is about 1700m.By using the method of hydrocarbon generation potential,the hydrocarbon expulsion intensity of the three sub sections is calculated.The hydrocarbon expulsion intensity of Niuxintuo sub section is 15×10⁴t/km²,which is far higher than the other two sub sections,which is the main oil generating section in the area.Niuxintuo sub section is also the main oil producing end,and the reservoir belongs to the source The average porosity of the reservoir is less than 12%,which is considered to be a tight reservoir.In the south central depression of Niuxintuo,it is a tight deep basin reservoir,ranging from well Tuo 25 to well Tuo 27,in the north central area it is a tight conventional reservoir,ranging from well Zhang 1 to well Tuo 12.Through hydrocarbon generation forward modeling and fluid inclusion inversion,it can be seen that the main reservoir forming period of the two kinds of reservoirs is in the late stage of Sha 3.The main reservoir controlling factors are tight conventional and tight deep basin reservoir controlled by reservoir,source rock and structural factors;reservoir physical property 5%<?<12%,distance from hydrocarbon expulsion center<10km,structural high point and fracture development area control tight conventional reservoir;reservoir physical property 5%<?<12%,distance from hydrocarbon expulsion center<10km,structural stability zone control tight deep basin reservoir.