Fracture Characteristics And Gas Relations In The Middle BaChu Uplift

Bachu uplift interrupt area with the formation of trap most closely related tofracture. Fracture identification and its evolution research is implement trap andevaluate the effectiveness of important factors and traps content. Current bachuinterrupt area Paleozoic zhang fracture is less. So, to bachu uplift interrupted thePaleozoic is broken sentenced to knowledge, evolution and the relationship betweenoil and gas comprehensive, systematic and in-depth study is very necessary.Based on the latest geological, geophysical data with plate tectonic theory asguidance, to the seismic interpretation as the main means to tectonic evolution as themain line, through the combination of geology and geophysics, summarizes differentfracture development evolution rule, system, fully recover the main movement period,analysis and fracture form evolution especially main fault fracture evolution andhydrocarbon accumulation relationship. District-based provide basis for the nextexploration. Made the following main conclusions and know:(1) According to the main fracture section of evolution and the main activeperiod fracture plane developmental characteristics, according to initial period andfinal fracture comparative analysis, finalize the design period will bachu uplift middleway fault activity summarized to the following four: (1) The one-time formation, lateragain the reform movement inactive fault; (2) The early formation and transformationof the fault inherits later time; (3) Formed earlier and later times the fault inheritstransformation; (4) Later reversed early stretch, renovation of the faults.(2) The research comprehensive utilization in seismic profile fault disconnecthorizon, from size, fault fault on the phenomenon such as wall thickness difference,quantitative calculation, and the fracture growth index change, at the same time cooperate tracking fall to change, special sedimentary system or phase transitionevidence, identify antique mountain YiNa, deep, Carla sand in north, vomit kara sand,wooden shock beihai millo 1, antique mountain 1 and so on a series of early arefracture.(3) Gudongshan deep, Carlashayi north, Carlashayi south,tumuxiuke northremained normal faults nowadays, often broken down into form with broken into thebasement, up most of the Cambrian strata, cut into the ordovician stratum, this kind offault activity period, not for Gary east early by tectonic movement significantly affectlater. HaiMi Ross 1, antique mountain 1 etc fault fault wear ordovician, continued tobe Gary east of hercynian tectonic movement period, the transformation, inheritancethrust, or even continued activities to Himalayan period.(4) The middle area of bachu uplift of early are breaking today, combined withthe main profile Angle statistics, detailed analysis of the evolution of early tensionalnormal faulting, found the dip Angle early extensional setting Gary east of tensionalnormal faulting development Angle 60°to 45°core, among them less than 60 earlyare fracture later have experienced reverse thrust, and reverse generated thrust faultdip larger, be in commonly 75°~ 80°Angle between more than 60°, and the earlytensional normal faulting, later there is no resurrection, surviving.(5) According to tectonic section evolution and tectonic style midway throughthe analysis will be bachu uplift the tectonic evolution stages division for Gary eastearly Middle East, Gary haixi early, late - late hercynian, seal teams yanshan periodand the Himalayan period - five stages, the tectonic activities in many times togradually change the early tectonic framework, late hercynian movement HeXiShanmid movement is main structural transformation period, and the end, the earlycarboniferous end and Miocene tectonic pattern of the change is three key moments.Early tensional normal faulting are fracture of the late period of its formationsedimentary up control effect; Is the basis of fracture evolution late, is now with theprototype of the fracture structure; Paleozoic tensional normal faulting are fractureaffected the local structures and traps later the formation of hydrocarbon migrationand can be used as the channel, the late Paleozoic tensional normal faulting along theeruption of the early Permian volcanic rock reservoirs to early form, played thedamage.