Structural Interpretation And Favorable Zone Prediction Of Jinzhong Block In Qinshui Basin

The area of Qinshui Basin is 36000km~2,and the exploration area of coalbed methane is 27100km~2,which is one of the best coal accumulating basins in china.Basin coalbed methane production is rich,accounting for ninety-three percent of the total domestic output,accounting for up to 1/10 of the total national resources,with a high value of exploration and development.Investigation stage mainly aimed at shallow depth of 2000 meters,the resource quantity is 39500.42 * 10~8m3,however,the amount of resources in the depth of 2000 meters below the not proven,for gas layer in the study area outside the conventional natural gas exploration has not been carried out.In recent years,a new round of coalbed methane resource potential evaluation results and the situation of regional energy gas exploitation,the natural gas resources in the basin has great potential for exploitation.Affected by the tectonic evolution of the North China platform,the Qinshui Basin experienced three stages of tectonic compression in the early Middle Jurassic,the late Jurassic Early Cretaceous extensional rifting and the Cretaceous Paleogene compression reversal.The Jinzhong block in the study area is located in the north of Qinshui Basin.The main tectonic events occurred in the Yanshan period.The tectonic development mechanism and fault distribution in the study area are the preservation conditions and migration pathways of oil and gas accumulation.Firstly,the fine structure interpretation is carried out,such as wavelet extraction,synthesis record,horizon calibration and tracking,time depth conversion,structure mapping and so on.Preparation of Shihezi Formation,Shihezi,Shanxi group Taiyuan Group Co,bottom four layers structural map.According to the fracture distribution and assemblage,tectonic setting and evolution,outcrop conditions,the main faults are determined,and the Jinzhong block is divided into four tectonic units of Jinzhong fault depression,Archean slope,Yushe slope,Wuxiang sag.Secondly,according to the tectonic evolution process and the regional tectonic background,the simulation experiment is carried out to verify each other.The essence of the structural simulation experiment is to simulate the actual geological structuredeformation by using the similar conditions,and to study the evolution of the structure,the cause of formation and the dynamic development.Through the comparative analysis of the experimental phenomena,can be seen that the influence of Early Jurassic to Middle Jurassic NWW compressional stress on the fault zone of the large SEE compressional stress influence is weak;in Late Jurassic to early Cretaceous period NWW tensile stress has a decisive role in the formation of Jinzhong depression.It can be inferred that the area affected by stress and boundary conditions in the main reservoir forming period(Yanshan period)is the Yushe.Compared with other tectonic units,the Yushe slope is far away from the boundary of the basin,which is the least affected by the boundary conditions.The slope of Yushe is located on the east side,and the influence of the stress condition is much lower than that of other tectonic units.Compared with the 2D seismic data,the slope structure of Yushe is relatively stable.The evolution of this topic and give full play to the main advantage of the fault structure modeling experiment,using seismic data interpretation and analysis of secondary fault features and combination,which combines the advantages,development mechanism construction area analysis.After comparison and analysis,it is concluded that the favorable zone of natural gas accumulation in the work area is on the Yushe slope structure belt,which provides the basis for the subsequent exploration and development of the basin.