Refined Evaluation Of Reservoir Parameters Of Putaohua Oil Layer In Yushulin Oil Field

Currently, the development, exploration and further reservoir evaluation is jointly conducted in the Putaohua oil layer of Yushulin oil field in the city of Daqing, a low-permeability oil field, which contains lithologic and fault-block reservoirs, with deep burial depths, small sand bodies, poor physical properties of crude oil and low natural production capacity. Therefore the complexity of the distribution of reservoir parameters leads to the difficulty in accurate identification of oil layer by means of logging.In this paper, Putaohua oil layer is determined as the target, on the basis of which demands of exploration and development, research aming to explain the reason of low consistency rate of log interpretation being carried out. After a series of petrophysical analyses, the characteristics of reservoir parameters and oil-water distribution are detailedly summarized in order to calculate each parameter and thereby establish reasonable oil-water layer identification plates, resulting in improving the accuracy of log interpretation of complex reservoirs in this region. Amid the course of the study, the reservoir’s porosity, permeability, with their parameters, and the effects of shale and calcium content are consolidated, by means of multiple regression, consequently calculating formulas are acquired.In the process of oil-water layer identification, in addition to conventional oil-water distribution layer, the causes of low-resistivity oil layer and high resistivity water layer in this region have also been analyzed so that the accuracy of oil-water recognition have been improved as well. Therefore methods of water saturation calculating are established, oil-water layer identification plates are drawn and consistency rate reaches to 87.93%.