Study On Remaining Oil Distribution And Potential Exploitation Of 32 Block In YM Oilfield

With the continuous improvement of proven hydrocarbon reserves, the remaining space of exploration is getting smaller, and exploration also increasingly become more difficult, so the study of remaining oil distribution and potential is of great strategic significance for an oilfield in the mid-late period of development. Block32of YM Oilfield, which was cut by multiple faults, is a carbonate buried hill reservoir with side and bottom water, having complex stratigraphic structure and serious heterogeneity. Currently, most wells in this block have high water cut, and the individual well producing rate decreases rapidly. Moreover, the movement of underground oil and water and distribution of remaining oil is unclear, so that the tasks of development adjustment are formidable.Further understanding of geologic features can be got by the information of drilling and completion, well logging and testing. According to static geological information like structure, stratum and reservoir characterization, a fine geologic model is built. Then, combined with reservoir production performance information, numerical simulation is carried on. Next, the volume of natural water body is determined by material balance method and transient water invasion method, and then this volume value is compared with that of reservoir numerical simulation. Finally, the characteristics of water invasion are analyzed, and the appropriate calculation method is determined.Based on the above studies, it is concluded that the influential factors of remaining oil distribution can be divided into two classes:(1) geologic (2) development. On the basis of the actual development status of block32, the main factors affecting remaining oil distribution include reservoir heterogeneity, faults, micro structure, interlayer and completeness of well pattern.An exhaustive study of block32is made by combining dynamic analysis method of reservoir engineering, fine geological model and reservoir numerical simulation technology. According to the study results, there are four main distribution types:(1) remaining oil without well network,(2) remaining oil controlled by faults and micro structures,(3) remaining oil controlled by edge and bottom water coning behavior,(4) shallow layers, thin stratum and scattered remaining oil. At last, corresponding potential tapping measures are made in accordance with the distribution type of remaining oil, and making the prediction and optimization by the use of some development plans.