The Tectonic Evolution And It's Controlling On Hydrocarbon In Wuxia Fault Belt Of Junggar Basin

On the basis of structural geometry, kinematics, dynamics analysis and theory of modern petroleum accumulation, this dissertation utilizes abundant fundamental data to study the law of tectonic evolution on trolling hydrocarbon in Waxia area. Combing faults zone features, structural evolution mode, fault activities controlling fans, and petroleum accumulation, the author establishes theory and method of tectonics controlling hydrocarbon.Wuxia area was located on the eastern of northwest Junggar basin, it was a zone of bruchfalten affected by multiphase tectonic activity, have many faults and its fold morphology were very complicated, underwent three large structural activities, which happened in the late Hercynian movement, Indo-Chinese movement, and the Yanshan movement, by this,strata of Wuxia area can be divided into two primary tectonic sequences and seven secondary tectonic sequences, on plane, Wuxia area can be divided into three secondary structural units from north to south,they are foreland thrust belt, Wuxia fault fold belt and monocline belt, further, from west to east Wuxia fault fold belt can be divided into four fault fold belts. As a result, strata distribution, kinds of sediment fill, oil and gas distribution vary in different structural unit and tectonic sequence.Faults are vertically subdivided into deep fault system and shallow fault system by the bottom of Jurassic Formation at Wuxia area. Because of multistage structural activities, fault activities are episodic. In whole, east-north and east-north-east faults activities were advancing in Permian, proximal east-west faults activities were retrogressive in Triassic and Jurassic, and they migrated from west to east, north to south, coincided with center migration of subsidence by subsidence curves.From structural geometry, Wuxia fault belt developed twelve structural styles, among them fault-propagation folds and buckle-propagation anticline are the most important. At early stage bedding fault activated, then transected strata to control formation of anticlines miniature, from late Permian to Jurassic growth faults controlled growth anticline, finally joined end to end, and merged to a common slip surface. At the same time, six kinds of growth sequence of structural styles are presented, coincided with the position of each structural units and accommodation zone.Then, associated with kinematic equilibrium section, compression ratio of basin, volcanics analysis, sedimentary facies distribution and tectonic-stress field, etc. model of structural evolution before Permian can be divided into five cycling of opening and closing campaign, from Permian to Jurassic will be divided four important structural evolution stages. At early stage of Permian, there developed a kind of especial foreland basin caused by soft collision effect, volcanic action occurred widely and probably relevant to deepen mantle-derived magma, further, based on formation thickness, sandstone analysis, mass transport direction, and sedimentary environment analysis, this dissertation studies framework of archetypal basin. Then through building modes of Mountain Hala'alat and faults controlling basin, it is thought that uplifting of mountain, subsidence of Wuxia fault belt and Heshentologa innertief basin have close relation to circle of landmasses, strike slip motion of marginal faults, so"Transpression Model"and"Differential Circling, Departure Up And Down Model"are proposed.Finally, from the point of structural evolution, at the base of"Theory of Fans Controlling Oil and Gas"and"Theory of Overlapped Faults Controlling Oil and Gas", the dissertation studies relations between faults activity and fans distribution, shows that structural evolution not only controls combination among oil resource rock , reservoir and cap rock, controlling types of traps and distribution of reservoirs, but also affects hydrocarbon accumulation phases, and that as a result, activate faults and unconformity surfaces selectively control and affect migration and accumulation. So, it can be said that tectonic features are the most important factors at the course of hydrocarbon accumulation undoubtedly.By the analysis of factors of hydrocarbon accumulation elements and hydrocarbon distribution features, the author establishes four models of hydrocarbon migration and accumulation types, which are the earlier model of lateral transportation through sandbody- unconformity, the multi-phase model of vertical transportation through fault, the multi-phase model of"z"type transportation, and the later model of stepped transportation.