Reservoir Rock Typing Method and Application Based on Geological and Petrophysical Features——Taking the Porous Bioclastic Limestone Reservoir in Iraq a Oilfield as an Example

In order to characterize the reservoir porosity-permeability relationship and water saturation or other petrophysical characteristics of bioclastic limestone reservoirs with complex pore types in the case of very few capillary pressure data available, this paper proposes a reservoir rock typing method based on Winland R35 and IPSOM algorithms. The geological facies of reservoir are identified on the basis of cores and thin sections data, and the petrophysical groups are divided on the basis of capillary pressure curve and porosity and permeability test data. Combining geological facies and petrophysical groups, the rock typing of cored wells is realized. Based on the IPSOM algorithm, the sample learning of cored wells is completed, and finally the propagation of rock types to non-coring wells is realized. This paper takes the porous bioclastic limestone reservoir in Iraq A Oilfield in the Middle East as an example. Through verification, it shows that this method can conveniently classify rock types, with an accuracy rate of more than 85%. It lays a foundation for the characterization of reservoir permeability and water saturation, from the core domain to well logging domain and the promotion of the three-dimensional geological model. The method is convenient and practical, which can be extended to other porous carbonate reservoirs for reservoir heterogeneity characterization.