Abstract: The prediction for the distribution of baffles and barriers is an indispensable part for the fine description of oil reservoirs in the middle-late stages of oilfield development,because the differential permeability caused by these layers has become an important factor affecting the distribution of remaining oil.As for complex and highly heterogeneous reservoirs,it is difficult to accurately and reasonably characterize their thin baffles and barriers simply by using the geological data of outcrop, limited vertical well data and geological experiences.As there are abundant horizontal well data available,we proposed a new idea and technical process to describe baffles and barriers by the combination of vertical and horizontal well data.The cross-plotting analysis technique of change amplitude parameter values of logging curves being sensitive to baffles and barriers was introduced into the technical process.The identification criteria of baffles and barriers and the method of predicting their occurrences with horizontal well logs under the constraint of seismic structural surfaces were used to establish the isochronous correlation framework and the relationship of logging responses of baffles and barriers between vertical wells(segments)and laterals,and to determine the types and quantitative interpretation standards of baffles and barriers in single laterals.Then the distribution of baffles and barriers along the trajectory of horizontal wells was discussed, and multiple data and geologic models were integrated to guide the correlation of baffles and barriers on profiles and the study of their planar distribution,and to verify and correct the previous interpretation results obtained based solely on vertical well data.Finally,the oil-water movement process and residual oil distribution and enrichment characteristics under the control of the baffles and barriers were comprehensively analyzed in combination with the dynamic development data.This study provides a powerful basis for the adjustment of subsequent oilfield development plans and the emplacement of new wells.

Key words: vertical well, horizontal well, description of baffle and barrier, oil-water distribution, remaining oil and gas, oilfield development