Research And Application Of Reservoir Prediction Method Of Channel Sands Based On High Density Three-Dimensional Seismic Data

Several nose-like structural belts developed in Jurassic Fudong slope of Junggar basin in Xinjiang with favourable exploration area of 2000km~2,which represented good petroleum geology condition and great resources potential.In recent years,commercial oil has been discovered in many wells in Jurassic Toutunhe formation such as Fudong 2 and Fudong 5,which showed that Toutunhe formation has a good prospect for oil and gas exploration.However,the Toutunhe formation is a setting of fan delta subaqueous distributed channel sediments,and sandstone reservoirs with generally water-sensitive and highly heterogeneous is characterized by complex multistage superimposed relations vertically and large changes of lateral lithology and thickness.It is difficult to predict high quality reservoirs in target strata because of the complex geological conditions and largebins of previous conventional seismic data,so the accuracy of hydrocarbon detection is low.In this study,the seismic pre-stack attributes analysis and inversion methods have been applied based on the new acquired high-density 3D seismic data of well Fudong 5 area.Firstly,the characteristics of high-density 3D seismic data and the seismic responds of effective reservoirs have been analyzed in detail.And petrophysical characteristics of the reseriors have been identified based on drilled wells,and the parameters and methods for describing the channel processing and channel sands reservoirs have been decided.Finally,the hydrocarbon in reservoirs has been identified by using pre-stack seismic simultaneously inversion and fluid substitution.By using proposed methods and workflow,the reliable and accurate results of effective reservoirs and the hydrocarbon characterization have been reached,which provided the basis of drill-well sits making,new geological knowledge accumulation and the application of new methods,etc..The series of technologies and workflows of suitable predicting Jurassic channel lithological reservoirs have been proposed and established in the study area,which mainly include four steps of“channel shape depiction-reservoir identification-hydrocarbon detection technique-effective reservoirs identification with high potential production”.Proposed technologies and workflows can solve the problems of the difficulty of predicting effective reservoirs and identifying the hydrocarbon in the reservoirs in the area,which settle the base of detail exploration of Toutunhe lithological reservoirs,further efficient and quick production in the area,and also support the sustainable development of Xinjiang Oilfield Company.