The Application And Study Of Seismic Prediction Technique For Turbidite Sand In Dong Ji Depression

The Dongji sub-sag is a secondary negative structural unit in the Dongying Depression.It is located in the northern steep slope zone of the Dongying Depression and in the transitional zone between the Lijin sub-sag and the Minfeng sub-sag.The exploration area is approximately 170 square kilometers.In the study area,a large number of slump turbidites were developed in the middle and lower sedimentary ages of the Shahejie Formation.The reservoirs have favorable conditions for accumulation and rich in oil and gas reserves.However,turbidite reservoirs have the characteristics of poor lateral continuity,deep burial,small individual,thin thickness and large variations.Some turbidites is covered with strong shielding layers,it is necessary to carry out a systematic and in-depth study on the seismic,logging and reservoirs characteristics of turbidite sand bodies in Dongji area.Applying different techniques and methods to propose a set of advanced,reproducible and practical methods and techniques.Predicting the zone of favorable turbidite reservoir in this area to guide the further exploration and development of this type of reservoir.In this paper,we first elaborated the research status of turbidite reservoir interpretation at home and abroad through domestic and foreign literature surveys.Then we systematically analyzed the characteristics of turbidite sand reservoirs of one sand group and five sand group through seismic fine interpretation based on the seismic data and well logging data in the study area,it provides the basis for follow-up research.Because there is a strong shielding layer above the one sand group reservoir,the information of the underlying reservoir is obscured,which is not conducive to reservoir interpretation and tracking.This paper uses the matched tracking anti-strong shielding technique to peel it off and enhances the amplitude characteristics of the sand reservoir,this conducive to the later attribute analysis and reservoir prediction.Through the comparative analysis of attributes,it is found that neither one sand group nor five sand group turbidite sand reservoirs has a good attribute corresponding to the reservoir.The attribute fusion technique is used to optimize the attributes of the reservoir and find it has good corresponding relationship between effect map and reservoir,and it has certain guiding value for the distribution prediction of turbidite sand reservoirs in the study area.Finally,this paper proposes to apply the trace integration technique to the interpretation of turbidite sand reservoirs.A more accurate interpretation effect is obtained through theoretical analysis and application in actual data.It is proved that the trace integration technique is validity to applied to prediction of thin turbidite sand reservoirs,and it is worth learning and popularizing in the future interpretation work.