A Research Of Reservoir Forming Conditions And Zone Evaluation Of Jiangling Depression

Jiangling depression is the main oil and gas accumulation and distribution area in Jianghan Basin.Jiangling depression has a low degree of exploration in general,uneven degree of exploration and drilling,large remaining resources,and still has great exploration potential and prospect.Due to the poor quality of seismic data in Jiangling depression,the understanding of geological structure and the depth of target evaluation are not enough.To clarify the basic petroleum geological characteristics and the relationship between the reservoir forming factors of each zone,deepen the understanding of the reservoir forming conditions,the law and scale of oil and gas accumulation,evaluate the exploration potential of the zone and optimize the favorable exploration zone.Through the detailed description and study of traps,the favorable targets of oil and gas exploration are optimized,the next oil and gas exploration deployment in the work area is guided,and the benefit and effect of oil and gas exploration are improved.In this dissertation,through the comprehensive study of the geological conditions of reservoir formation in Jiangling depression,the theory of multi-source mixed reservoir formation is applied to analyze the controlling factors of reservoir formation in each zone,to predict and establish the three-dimensional reservoir formation combination model of multi-layer system,and to use the trap description and evaluation technology to accurately describe the favorable circle of each zone.According to the research results of resource evaluation and trap description evaluation,the resource reserve sequence of each zone is established,the zone and exploration target are optimized,and the exploration deployment is guided.Through the research,we get the following cognition:1.Jingzhou anticline zone and Wancheng fault zone are favorable for exploration in Jiangling depression,and Gongan monocline zone is more favorable.2.The law of oil and gas accumulation in Jiangling depression:favorable hydrocarbon generating syncline and its surrounding area are the main areas of oil and gas accumulation;the delta front facies belt of Xingouzui Formation is the main area of oil and gas accumulation;the fault controls the three-dimensional distribution of oil and gas,and the hydrocarbon generating depression and its surrounding fault ascending disk of a certain scale are the main areas of secondary oil and gas accumulation;The trap type controls the hydrocarbon accumulation type and degree.3.The evaluation of the area(block)is carried out by the method of scoring the geological elements and queuing the comprehensive evaluation coefficient of the formation conditions.The area of class ? is Fuxingchang Shashi block in the middle of Jingzhou anticline;the area of class ? is divided into four areas(block)including Balingshan Huayuan block in the north section of Jingzhou anticline,Wancheng fault zone,Gongan Jinjiachang block and Zifusi syncline zone,and the area of class? is Jingzhou Fanjiatai block,Shiqiao monocline,Qingshuikou syncline,Jiangkou syncline and Shadaoguan block in the east section of zhouanticline belt.1.Class ? block has not only good reservoir forming conditions,but also great resource potential and multiple reservoir forming combination conditions.It is a favorable place for oil and gas accumulation in Jiangling depression and a favorable block worthy of exploration in the future.