Resource Potential Evaluation And Favorable Exploration Areas Prediction Of The Shale Gas In Upper Paleozoic Taiyuan Formation In Ordos Basin

Based on the full investigation of the shale gas research findings at home and abroad,and by means of comprehensive utilization of field outcrop observation,drilling data and sample testing data,as well as in-depth analysis of oil and gas exploration information and shale gas reservoir geological characteristics in study area,petroleum geology,sedimentary petrology,geochemistry and so on research methods are combined with qualitative and quantitative analysis methods being well used,the resource of Taiyuan group shale gas in Ordos basin was calculated and the favorable exploration areas of the Taiyuan group shale gas are selected.In Taiyuan group of Ordos Basin,the geological conditions of shale gas is good.The shale of Taiyuan group belongs to transitional faces deposition,the formation is mainly mudstone,sandstone,coal and limestone.With moderate buried depth,the embedded depth of the shale is 1500m?3750m in the main part of the basin;Except some areas in the south,shale distributed widely in the basin,the vertical accumulative shale thickness is up to 90m in max.The Taiyuan group shale has high organic matter contents,of which TOC is generally between 1.0%and 6.0%,with a trend of lower values in the southwest of the basin and higher values in the northeast of the basin.The shale also has high maturity of organic matter,and Ro is generally between 1.0%and 2.2%,and the Ro of Taiyuan group is high in the southwest of the basin,but the northeast of the basin in plane shows higher maturity of organic matter.The result of rock pyrolysis analysis shows that organic matters are mainly in type? 1,? 2 and ?,partly in type I.And the data of X-ray diffraction analysis indicates that the shale has High brittle mineral contents,which usually rang from 35%to 65%.A great deal of predecessors' research shows that the main basin has nice tectonic stability,which is favorable for the shale gas preservation.Resources calculation results show that the Taiyuan formation has some potential.The shale gas of Taiyuan group can be another exploration target in Ordos Basin.According to evaluation criteria,the Taiyuan formation is divided into two shale sections of the shale,in order to better evaluate resources potential.Shale gas resource potential of the second layer is better than Shale gas resource potential of the first layer.Two favorable areas are selected in the first layer optimization,and two areas favorable in the second layer.The geological resources of shale gas in Taiyuan is about 2.088 trillion cubic meters.Favorable exploration areas of Taiyuan group mainly concentrated in the east of Tianhuan depression and the area near Shenmu,and the geological resources of favorable exploration areas is about 0.47823 trillion cubic meters.