The Source Kitchen And Hydrocarbon Accumulation And Migration In Honghaoershute Sag,Erlian Basin

The Honghaoershute sag is one of the oil-rich sag in the Erlian Basin.In recent years,the exploration potential of the oil and gas resources in the Honghaershute Sag is huge.Aiming at the problem that the quantitative analysis of the source of the sag is not clear and the relationship between the reservoirs is not clear,this paper will study the evaluation of hydrocarbon source,the history of thermal evolution of source rocks and the relationship between the reservoirs.Combining the organic geochemical characteristics of the source rock with the sedimentary environment to identify the organic phase of the source rock,the grading evaluation of the source rock can be achieved,and the spatial distribution of the source rock is determined.Using the vitrinite reflectance,biomarker parameters and alkane parameters to demarcate the maturity threshold of organic matter of source rocks,the effects of surface temperature,paleogeothermal gradient and denudation of denudation on the geotemperature field in the study area are comprehensively considered,and the maturity of organic matter in source rocks can be finely calibrated degree.The results show that the main hydrocarbon source rocks of the Honghaoershute Sag are the lacustrine dark mudstone of the Cretaceous A'ershan Formation?K₁ba?and the Tenggeer Formation?K₁bt?.According to the good correlation between total organic carbon content of source rock and hydrogen index,the grading evaluation of source rock heterogeneity can be realized.Through the study of regional stratigraphic sequence and sedimentary environment,the main sections of A'ershan?K₁ba?Formation and Tenggeer Formation?K₁bt?developes organic phase C and D/E source rocks,and determine the source rock thickness distribution model.According to the thermal history model,the source rocks of the A'ershan Formation?K₁ba?are in a mature stage,and Ro in the centers of subsurface depressions can reach1.0%.The source rocks of the K₁bt₁ are in the immature?mature stage,and Ro in the center of subsurface depressions is 0.7?0.8%.Using the software of Trinity 3D oil and gas system,the hydrocarbon expulsion intensity of hydrocarbon source was evaluated finely.The emission intensity of hydrocarbon source in A'ershan?K₁ba?was 2.0×10⁶?2.6×10⁶ t/km²,and the emission intensity of source rocksreservoirs have the characteristics of“near-source accumulation”and the favorable oil and gas exploration areas is predicted.