| In recent years, the sequence stratigraphy has been more concerned by most people with the theory development. Now it has become a successful technique and powerful method in searching for oil and gas, which take more effect in petroleum exploration and exploitation. With the exploration degree improved gradually in oil fields, it becomes more and more difficult to add and find new structure trap, and the traditional theories of exploration becomes no use. As a new theory and method, the sequence stratigraphy has shown its advantages in search of subtle traps.The study area, Gubei slope is situated in Zhanhua depression, Jiyang subbasin, Bohaiwan basin, which lies between Gudao uplift and Gubei depression, the area is about 100km2. Up to now, this area has been drilled into part of the Mesozoic, Shahejie Formation, Dongying Formation, Guantao Formation, Minghuazhen Formation and Pingyuan Formation of the Tertiary. The target stratigraphy is Sha-2 Formation and Sha-3 Formation and the study task of the thesis is to make high frequency stratigraphic classification, and to build spatio-temporal stratigraphic framework, as a result, spatial distributing and evolvement process of the sediment formation could be recover, and favorable oil and gas trap could be predicted with the help of the data analysis such as seismic section, well logs and core. Gubei slope locates in the middle structure area of Bohaiwan basin which stretch toward near north and south, and the faults which tend towards east and west spread all over of the whole district. Three huge faulty trap which control the sediment formation growth distribute in order, which result in the stratigraphy dropping in step along the slope. In this condition, applying the theory on searching for oil in faulty-step break to direct exploration must acquire good effect.Near the faulty step-break, low stand system developed, and some sediment system distribute broad, such as alluvial fan, low stand wedge, low stand fan, and so on. The sand body can form not only the trap of dying out upward and sand lens, but also fault-Iithology trap. The study shows that fault-lithology trap is most important trap style in study area especially Sha-3 Formation. Commonly the sand body of low stand system developed, which can act as excellent oil reservoir. But, because the exploration exists larger dangerous in low stand system, it is not thought much.the study area was studed in sequence stratigraphy which was directed by the theory of H.Posamentier, and high frequency sequence stratigraphic framework was built base on seismic and drilling analysis, furthermore, cooperating the interpreted result of seism and drill to identity and divide sediment facies can recover paleogeomorphic and paleogeographic environment, and predict profitable oil trap.The result of data analysis and studying shows that the low stand system of down-Sha-3 Formation, the high stand system of mid-Sha-3 Formation and the low stand system of up-Sha-3 Formation are important to form subtal trap.This thesis predict profitable oil trap under the direction of the theory on searching for oil in faulty-step break, and select classy from them in terms of the style, scale, reservoir factor and shelter of the sedimentary sand-body distributing. Take the low stand system of down-Shasan Formation for example, three favorable targets was put forth through synthesis analysis.
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