Development and identification of petrophysical rock typing for effective reservoir characterization

Abstract

Rock typing is an essential tool used to distribute reservoir rock and fluid properties in reservoir models. It provides more accurate estimates of oil reserves during field studies and prediction of reservoir performance. These properties are required inputs for static and dynamic models to populate porosity, permeability, and shale volume which influence reservoir productivity. During field development studies (FDP), the technical main aim is to design a fit for purpose project within budget to produce commercial volume of hydrocarbons in the field and reduce residual oil in the reservoirs. However, geomodellers frequently faced challenges in integrating geological facies with rock characteristics and fluid flow to predict petrophysical properties due to limited correlation between geological features and engineering concepts. This thesis examined Petrophysics rock types based rock classification scheme by comparing the approaches using rock samples. Among the trimmed approaches are Hydraulic Flow Unit(HFU), Global Hydraulic Elements(GHE), Winland R35, Pore Geometry Structure (PGS). Also presented is the use of electrical and nuclear log data obtained from the well Neutron-Density to produce relationships that tie pore geometric attributes, pore structures, and hydraulic flow characteristics. The study selected Hydraulic Units and GHE methods among others to be robust in Rock Typing based on consistencies observed between porosity and permeability relationships in typical clastics reservoirs. Thus, it reduces the uncertainties in reservoir models. Using capillary data to derive saturation height functions, the Hydraulic units demonstrated consistent results of rock types that integrates geological description with engineering hydraulic features.