Jurassic Oil And Gas Formation Pattern In The Northern Piedmont Belt Of The Turpan-Hami Basin

As one of the most important oil-gas-rich structural belts in the Taibei Sag of the Turpan-Hami Basin,the northern piedmont belt is a complex thrust fold system based on thrust faults and strike-slip faults.The following problems:(1)The structure is complex,with the characteristics of zoning and zoning;(2)The oil-water relationship is chaotic and affected by multiple factors,and the law of oil and gas accumulation is unclear.The Jurassic is the stratum with the most complete sequence development,the widest distribution and the highest degree of exploration and research in the northern piedmont belt,and no major new oil and gas discoveries have been made in recent years.Based on the unclear understanding of the distribution characteristics of oil and water in the northern piedmont belt and the law of oil and gas accumulation,this paper is based on seismic data,guided by petroleum geological theory,combined with regional structural development characteristics and sedimentary evolution background,and synthesized the structures of different structural belts.According to the characteristics of oil and water development,the regional structural characteristics of the northern piedmont belt were clarified,the oil and water distribution characteristics and regional accumulation rules of different structural belts were determined,and then the oil and gas accumulation model was established,and finally the favorable exploration areas were selected.Based on the seismic data of the northern piedmont belt of the Taipei Sag in the Turpan-Hami Basin,combined with the regional tectonic development characteristics and sedimentary evolution background,and applying the theories of fault-related folds and differential deformation of tectonic transition zones,this thesis proposes that the northern pre-mountain belt has the tectonic characteristics of "north-south divide belt and east-west segmentation",divides it into three different thrust zones in the north and south,and four tectonic zones from east to west,and clarifies the tectonic patterns and distribution rules of different tectonic zones.Combining the logging,seismic and development dynamic data of more than 80 wells and the characteristics of tectonic and reservoir development of four tectonic zones,the reservoirs in the study area were divided into three categories: tectonic,lithological and composite reservoirs based on the development characteristics of more than80 wells,4 tectonic zones and traps.Furthermore,based on the fault development characteristics of different tectonic zones and the oil-water distribution of key strata,it is concluded that the hydrocarbon accumulation in the northern piedmont belt is mainly controlled by four major factors: source rock,reservoir,capsular and fault,and the fault plays the dual role of conduction and plugging.Based on the above results,the two hydrocarbon accumulation modes of thrust fracture control reservoir and strike-slip fracture reservoir control were clarified,and finally the favorable target area was predicted.This study not only has the practical significance of ensuring the stable production and increasing production of oilfield and guiding the increase of reserves and production in oilfield,but also helps to further clarify the structural deformation structure of the northern mountain and its control effect on oil and gas accumulation and enrichment,and can improve the prediction level of oil and gas distribution,which has important theoretical significance for enriching the theory of fault control and reservoir control and faults in the piedmont belt.