A Study On The Relationship Between The Low-High Structural Pattern,the Fault Characteristics And Hydrocarbon Reservoir In Yingxiongling Tectonic Zone

Yingxiongling tectonic zone of the Qaidam Basin is a hot area of oil and gas exploration in the western region of China.Its structure is complex and the types of oil and gas reservoirs are various.So the research is of great significance.Based on basic map,3D seismic and well logging data,this paper divided the structure of the low-high tectonic pattern of this range.On the basis of the low-high tectonic framework, the structure of the main control fault section and the relationship between the two sides of the fault are studied.Then analyze the relationship among the characteristics of faults in different tectonic zones and the distribution of the hydrocarbon reservoirs.and provide some theoretical basis for the oil-gas exploration in the late stage of this region.This article mainly obtains the following understanding:(1)In accordance with the low-high structure,from the northwest to the southeast,the main hydrocarbon source rocks(E32) in this area can be divided into five concave-uplift area,they are Rao Qigequan concave-uplift area,Huan Youyuangou-Shizigou concave-uplift area,Huan Youshashan-Gasikule concave-uplift area,Huan Yingdong concave-uplift area,Rao Wunan concave-uplift area.They are located in the northwest of Yingxi,in the mid-east of Yingxi and northwest of Yingzhong.in the east and south of Yingzhong,in the nouthwest of Yingdong,in the southeast of Yingdong.(2)According to the section structure and the section shape.the faults in this area are divided into three types.They are single direction fault,Z-shaped fault and arc fault.FNl,Shizigou,Youshashan fault are single direction fault,they are inclined in one direction.the top and bottom of the section are parallel to each other. Shibei fault and No.? fault are Z-shaped fault,the shape in the seismic profile are similar to the word "Z",two tendencies appear in the opposite direction,the top of the section is approximately parallel to the bottom. FA1,FA2,FA3,FA4,FA5 fault are arc fault,section structure and section structure of these fault are synclines form,low in the middle and high around.(3)In Huan Youyuangou-Shizigou concave-uplift area,the section of FN1,Shibei,Shizigou fault are located in the northwest,southeast and northwest, the top are located in the southwest, northeast and southwest boundary;the section of FA1,FA2,FA3,FA4,FA5 fault can spread to the southeast of the area gradually,the high position is basically located in the northwest of the area.From the northwest to the southeast,No.? and Youshashan fault section runs through Huan Youshashan-Gasikule concave-uplift area and Huan Yingdong concave-uplift area,the top of the No.? fault is located near the northeast edge of the area,the top of Youshashan fault is located in the middle of Huan Youshashan-Gasikule concave-uplift area and near the southwestern border of Huan Yingdong concave-uplift area.(4)The relationship between the two sides of Shibei fault are in accordance with the distribution of half-ridge-half-valley of the same tendency,half-ridge-half-valley of the reverse tendency,half-ridge-half-valley of the same tendency(parallel ridge of the same tendency) from deep to shallow.The relationship between the two sides of Shizigou fault are in accordance with the distribution of parallel shape,half-ridge-half-valley of the reverse tendency from deep to shallow. The relationship between the two sides of Youshashan fault are in accordance with the distribution of parallel shape.parallel ridge,half-ridge-half-valley of the reverse tendency from deep to shallow.The law of the bilateral strata relationship of FN1 and No.? fault are not obvious,mainly half-ridge-half-valley and parallel shape.The bilateral strata relationship of FA1,FA2,FA3,FA4,FA5 fault are parallel shape basically,parts are half-ridge-half-valley.(5)The distribution of oil and gas reservoirs in this area is very consistent with high point position of the No.?,FA3,FA4,FA5 fault.They have a high degree of agreement. It is proved that the oil and gas reservoirs in this area are often located in the high position of the fault section.Compared with the well date and seismic data,four types of oil structures are summarized,they are valley like monoclinic and anticline associated with fault,high point of arc fault structure,tendency turning point of Z-shaped fault,convex lens type structure.