Fluvial Reservoir Flow Unit Study

At present, study on reservoir flow units is a hot spot and difficult thing in fine reservoir description. Based on the case of the 2nd oil group of Dongying group the 3 rd member in the 39th fault-block reservoir in the Huabei oil field, the characteristics, distribution and application of reservoir flow units of fluvial facies have been researched in detail.In the dissertation, first analyze the geological features of the 39th fault-block reservoir in the Chaheji oil field; then research the theoretic base of reservoir flow units in detail, including the macro and micro characteristics of fluid percolation, the features of flow units and relative concepts, the hierarchy structure of flow units in clastic rock, the genesis and affecting factors of flow units and so on, which not only defines the properties of flow units, but also sets forth the difference and relation of these concepts and relative research methods such as sediment micro-facies, architectural elements, petrophysical facies, lithofacies, diagenetic facies and single sandbody. According to the properties of flow units, by the idea of hierarchy analysis and the method of multi-discipline integrity, place emphasis on the study on the flow barriers of flow units, the choice and acquirement of characteristic parameters reflecting the properties of flow units, the classification of flow units in single well, identification of flow units in multi wells, the prediction of inter-well, the production performance of flow units and the relation between flow units and remaining oil distribution. At last, apply the study to development.The study indicates muddy interlayers and sealing faults are the largest part of flow barriers in the Cha 39th fault-block reservoir. The method of system clustering is better than other methods and the reasonable clustering number is 4, because of distinct difference within all kinds. The method of discriminant gets better result than other methods of pattern reorganization, fuzzy comprehensive judge and grey correlation identification. The distribution of flow units shows the kinds of flow units G and M are wide while flow units M and P are narrow. The flow units G and E distribute mostly in the channel bar and the flow units M and P mostly in two flank of channel. Based on the study results, somemeasurements to improve recovery have been brought about.Through such the study, an integrated and systematic thinking route and many methods of flow units of fluvial facies, even of non-marine clastic reservoir, have been put forward, which constructs and perfects relative knowledge structure. The thinking route and methods of study on flow units are good reference to other continental reservoirs.