Study on 3D Micro-pore Structure Characteristics of Dolomite Reservoir with Different Scales

Abstract

an-Abstract Tight dolomite reservoir microscopic pore structure characteristic is the key factor to explore this kind of unconventional reservoirs. In this paper, 3D high resolution reservoir characterization technique based on Micro - CT imaging, constant-rate mercury injection, high-pressure mercury injection and low-temperature nitrogen adsorption test technology are applied to study the micro-pore textures characteristics for T12C well Tanggu, Dagang oilfield with different scales. Through Micro-CT scan imaging, image processing, 3D visualization, porosity calculation and pore structure parameter reconstruction, it is concluded that Micro - CT imaging can directly reflect the changes of fracture and pore in 3D space; the pore radius distribution are close to the result of constant-rate mercury injection and high-pressure mercury injection method, wider than that of low-temperature nitrogen adsorption test; compared with these three methods, the porosity range obtained by Micro - CT imaging technology is slightly narrow. Thus, in order to be effective, comprehensive and accurate to characterize different scales microscopic pore structure characteristics of tight dolomite reservoir, it is better to integrate these four methods.