ICE 2022

Summary

It has been proven that digital rock physics (DRP) is a robust tool to predict rock properties, investigate flow mechanisms in rocks, and figure out the impact factors of petrophysical properties. Nevertheless, the comprehensive analysis of the effects of diagenesis on rock properties using DRP has not been reported. During the formation of sedimentary rocks, they may experience various diagenesis events, e.g., cementation and dissolution, which lead to chemical and physical reactions. Such reactions have a significant effect on rock properties. In this talk, we present a comprehensive investigation of the effects of diagenesis events and diagenesis pathways on rock properties. Firstly, we will propose a robust method to construct the original rock model which integrates the discrete element modeling method, quartet structure generation set algorithm. Then, the original model similarly undergoes four diagenesis events (two cementations and two dissolutions) along with two different diagenesis pathways for generating new models. Finally, some properties of pore space, transport, and elastic of all the models are analyzed and compared to investigate the effects of diagenesis events and pathways, including porosity, fractal dimension, two- and multiple-point correlation functions, pore and throat size distributions, coordination number distribution, tortuosity, absolute permeability, velocity field distributions of single-phase flow simulation, formation factor, and elastic moduli. The comparisons indicate that the sample that experiences the cementation and then dissolution exhibits larger porosity, fractal dimension, aperture, coordination number, and permeability, and smaller tortuosity, formation factor, and elastic moduli than the one which undergoes the dissolution and then cementation. Thus, understanding the sequence and magnitude of the diagenesis process can help us to better predict the flow and mechanical properties of rocks without conducting extensive experiments and computations.