Analysis Of The Proterozoic Thermal History And Petroleum System In The Basin Erdos

The Mesoproterozoic is the potential stratum of gas accumulation and production of Changqing Oilfield in Ordos region.However,there has been less study on the thermal evolutionhistoryof source rocks for a long time.In this paper,with the application of PetroMod basin modeling software,basing on the analysis of lithology,erosion thickness restoration,ancient heat flow,taking the measured Ro values as calibration,using the EASY%Ro model proposed by Sweeney and Burnham,the thermal evolution history of Proterozoic source rocks has been simulated in the single and two-dimensional seismic sections of each tectonic unit of this region,it analyzes the differences of thermal evolution of source rocks in different tectonic units,and combining with the oil and gas system analysis,the favorable exploration areas have been predicted.Achieving the following understanding:(1)The geothermal heat value of the Ordos basin in the Mesoproterozoic period has changed slightly,and the geothermal value changed little from Proterozoic to Permian,with an average of 61 mW/m2,and the Mesozoic Triassic increased slightly,with an average of 66 m W/m2.The geothermal heat flow is basically between 75 and 92 mW/m2 from the Late Jurassic to Early Cretaceous,and the average geothermal value in the basin is 62.67mW/m2.There are obvious rationalities in the current heat flux of the earth,and the whole has the characteristics of low east and low north.(2)The thermal maturity history of the Proterozoic hydrocarbon source rocks in the Ordos Basin has shown that the uplift of the Mesozoic paleo-hydrocarbon source rocks in the uplift area is later than that of other regions,The Mesozoic lithofacies in the western part of the basin and the valleys in the basin and the surrounding area are mature,and the middle and lower source rocks are mostly in the mature stage.The upper source rocks are mostly In the eastern part of the Mesozoic source rocks are basically in the Permian into the hydrocarbon threshold,most of which is in the dry gas stage.(3)The source rocks of the Great Wall are medium source rocks,which are partially hydrocarbon source rocks with good hydrocarbon generation potential.The source rocks of the Jixian County belong to the poor-medium source rocks,but little of them can be the mediumand good source rocks individually.All of them have a certain hydrocarbon potential.(4)In the basin,there are three types of reservoirs in Proterozoic and Ordovician.Among them,the favorable laterly migration reservoirs of three reservoirs are mainly located in the central and western regions of the Yimeng uplift.The self-generated reservoirs in the Jixian County are mainly located in the Qingyang paleo-uplift area.The self-generated reservoirs in the Great Wall are mainly located from the central-western basins to the Wushenqi area and the south of the basin Chunhua,and to Chengcheng area.