Tahe Oilfield Tectonic Evolution And Hydrocarbon Accumulation Process Dynamic Simulation

Tahe oilfield, located in Akekule swells of south flank of Shaya uplift in northern Tarim basin, is an Ordovician system carbonate rock reservoir. It is the first Paleozoic erathem marine faces oil field that has been found in China, the reserve volume verified has exceeded one billion tons by far. With the depth and expansion of the exploration of Tahe oilfield, the recent discovery of the oil and gas in Aiding area better proves that there are good oil and gas accumulation conditions around the outskirts of Akekule swells. A paleostructure-based structural evolution study could help people to learn about the formation of Akekule swells in a general way, and this could provide background knowledge and elemental information for the exploration in the next step. Therefore, it is necessary carry out the study of erosion recovery amount of Akekule swells in different periods and the features of the paleostructure in a deep-going way, and summarizes the tectonic evolution model on this basis. Tahe oilfield Ordovician reservoir is a large-scale karst seam hole type reservoir, with a component model of‘Ordovician karst- seam hole-compounding structure reservoir pattern’and‘Triassic tectonic-Lithology composite reservoir pattern’, they are typical patterns both home and abroad. The vivid visual expressions of reservoir pattern are not only of great importance to the analysis of related complicated scientific questions, but also to the understanding of accumulation conditions for oil and gas in other regions. Through the studies of paleostructure features, erosion recovery amount of Akekule swells in different periods, and the features of structural evolution, this thesis analyses and collects the information of entrapment contained in different blocks and positions of reservoir-forming period, oil and gas injection period, and two-dimensional, three-dimensional dynamic demo models are provided. On the basis of these model scripts, two-dimensional and three-dimensional soft wares are used to perform simulations, so as to illustrate the structural evolution, precipitation features, oil and gas reservoir characteristics and filling modes etc. These simulations also give close-up illustrations of karst oil and gas formation in different periods, such as Gary east period, Hercynian, Yanshan - early Himalayan movement period and Late Himalayan movement period and so on. Detailed depictions of the formation mechanisms of karst caves in the Devonian are also given.