Study Of Deep Oil/Gas Prediction In Shiwu Fault Depression Of South Songliao Basin

Shiwu Fault Depression is located in the southeast uplift of Songliao Basin which can be distinguished into deep, middle and shallow exploration strata. After more than 20 years’ development to the middle and shallow layers, new discoveries are becoming less and less. So the deep exploration is becoming more and more important.The thesis belongs to practical research, and paper research contents geophysics and petroleum geology. Firstly, System study of depositional systems based on the study of sequence stratigraphy framework in Shiwu Fault Depression and deep strata depositional(below the Denlouku Formation), to determine the structural evolution and distribution regularities; Secondly analysis migration accumulation rules and main control factors and sum up accumulation mode of oil/gas by using the petroleum system; Finally, carried out a full range of three-dimensional display of the potential exploration targets by using geophysical techniques based on the petroleum research above, then combining with seismic response of oil/gas to make predictions for hydrocarbon exploration target in deep layer.Because of deep oil and gas buried deep, there is great difficulty of exploration. Combining advanced petroleum accumulation with modern geophysical exploration technology is the key to solve the problem of deep exploration. This thesis consists of mainly are as follows: 1.Studying of structural features and tectonic evolution of the fault depressionMake full use of the existing 3D seismic data and drilling data, On the basis of the combination of well and seismic, Determin the structural characteristics of the top surface of the main standard layers through referring to the achievements of predecessors.Tectonic evolution and its control of sedimentary filling. Analysis of tectonic dynamic background at different stages to create fracture system diagram through make full use of the 3D seismic data to zoning, grading and classification of above level 3 fault of the Lishu fault depression. On the basis of the above, summary of the filling characteristics of different tectonic zone in the plane, establishment of basin filling model in different evolution stages in vertical direction. 2.Studying of high resolution sequence stratigraphic framework3D seismic survey line profile combining with well-connecting seismic line、well log、drilling facies histogram and synthetic seismogram, was divided into tectonic sequence、 sequence set、 third-order sequences and lower level sequence units through Sequence stratigraphic subdivision. On the basic of this, focusing on the depositional System tract and system structure characteristics. 3. Studying of the seismic response of oil/gas in the deep layerCombining the research on deep seismic attributes and seismic inversion techniques with the logging response of deep oil/gas reservoirs, Geophysical response model of oil/gas in the deep layer of Shiwu Fault Depression; Establishing the lateral prediction model of deep oil/gas reservoir which can provide basis for evaluation and optimization of exploration targets. 4. Prospective area prediction, evaluation and optimization of exploration targetMainly focus on important region of favorable geological structure(carrier bed like discontinuous interface and sediment sand body, unique geological structure eta al), then use 3D seismic inversion technique to distinguish and detect the strata and the structure- the favorable region formed by lithologic oil/gas reservoir.