The Study On The Fracture Characteristic Of Low Convex Belt Of Xiayan In Luxi Area Of Junggar Basin

Xiayan low convex belt is located in the western section of the Luliang uplift in Junggar Basin,with a small fracture and micro fracture development,small fracture oil control effect in this area.For the difficulty of the recognition of controlling small fracture in Low convex belt of Xiayan,we formed a set of recognition method,including forward modeling,horizontal combination and attribute fusion,to improve the interpretation accuracy of small fracture,to rediscover the fracture system,and to provide the structure foundation of Xiayan's overall convex anatomy.By the comprehensive analysis of the features of the discovered oil-gas reservoirs and factors control reservior controlling factors in Xiayan low convex belt,we cleared that the types of oil-gas reservoir are mainly the fault block reservoir and the fault-lithologic reservoir.The reservoir characteristics can be summed as "step-type reservoir,a hidden piece" and well interbedded sandstone and mudstone small fault sealing property.The reservoir controlling factors are main the fault sealing and the development of sand body reservoir,which is summed up as “fault control reservoir,sand body oil control.” The study on fracture screen profile and evolution characteristics,it is two development fracture,one is for the former early Yanshan's thrust faults with fault displacement in the carboniferous and permian;the other is for normal fault of Yanshan epoch,disconnecting horizon for Trias and above the horizon with small slip.From the analysis of the fracture plane strike,it mainly breaks in east-west and east-north and is consistent with the trend of the carboniferous and permian tectonic background in this region,which shows that the tectonic pattern of early Hercynian movement affect the structure of the Yanshan period.