Prediction Of Reservior Sandbody Of Fuyu Oil Layer In Yuan 13 Block Of Toutai Oil Field

The Totai oilfield is located at the west end of the Chaoyanggou ground in the central depression of the Songliao Basin.It is a nose-like structure that plunges westwards.The noseshaped structure is a tertiary structure inherited and developed in the ancient central uplift zone.The Fuyu oil layer belongs to the Lower Cretaceous.In the fourth member formation of Quanquan Formation,the source 13 block is located in the northern part of the oil field.The Fuyu oil layer is controlled by surrounding sources to form intricate distributary channel sand bodies.The channel sand bodies are mainly strips,and the scale of the channel is generally small,and the sand bodies are relatively small.Thin,poor physical properties,and deep burial strata,strong late diagenesis,small differences in formation wave impedance,seismic wave reflection characteristics are not obvious,increasing the difficulty of sub-stratification,thereby affecting the prediction of reservoir sand body distribution and The determination of the distribution of oil and water leads to poor development.In this paper,based on the sedimentary study of the source 13 block in the past,through the combination of well-shock and small-layer contrast,the isochronal stratigraphic framework and two-dimensional fine-layer interpretations were established.The application of seismic attribute extraction and geostatistical inversion to Fuyu Reservoir prediction in reservoirs has higher inter-well sand body prediction accuracy and longitudinal resolution,which improves inter-well prediction accuracy and further improves development results.The results show that by carrying out joint seismic strata and establishing a unified stratigraphic framework,the Fuyu oil reservoir is divided into three oil reservoir groups from top to bottom,namely,FI,FII,and FIII groups with a total of 18 small strata.Using seismic attribute extraction,it is found that the seismic attributes have a certain guiding role for reservoir prediction of the Fuyu oil formation,and have good recognition and prediction effects in local areas where the sedimentary environment is relatively single and the seismic data consistency is good,and can identify the main stream direction and In the distribution range,the Fuyu oil reservoir belongs to the thin-bedded mudstone interbedded sedimentary characteristics.The single-layered sandstone deposits are thin and the lithology is mainly fine-grained sandstone.Therefore,the sand-mudstone velocity difference is small,and the direct seismic recognition rate is low.River channel sand bodies cannot be semi-quantitatively identified and described.Using the inversion results,the sand body of the oil-bearing layer is characterized.Compared with previous studies,it is found that the inversion of reservoir predictions is highly consistent.Using the results of seismic inversion of reservoir prediction,combined with the characteristics of structural development in the region,the area with strong potential for this area was optimized,and 6 well sites were designed and deployed.