Investigating Effects of Structural Deformation Regimes on Mineralization Distributions in Fluid-Saturated Rocks: Computational Simulation Approach through Generic Models

Abstract

Structural deformation regimes in the upper crust of the Earth can have significant effects on the distributions of pore-fluid flow in existing fissured and fractured zones, which are surrounded by fluid-saturated porous rocks. Based on the modern mineralization theory, mineralization distributions in ore-forming systems depend strongly on the distributions of pore-fluid flow velocity. Therefore, different structural deformation regimes associated with mineralization systems can remarkably affect mineralization distributions in existing fissured and fractured zones. This article utilizes a computational simulation approach, which is rigorously developed on the basis of fundamental scientific laws and principles, to solve coupled rock deformation, porosity–permeability evolution and pore-fluid flow problems, which are deeply involved in rock deformation driven mineralization systems. In particular, the porosity and permeability variations, which are caused by rock deformation, and often neglected in the previous studies of solving mineralization problems, are explicitly considered in the computational simulation approach of this study. The proposed approach is verified through a benchmark problem and, moreover, it was employed to examine how different structural deformation regimes can affect the mineralization distributions in existing fissured and fractured zones within the surrounding fluid-saturated porous rocks through using a generic model, which can be viewed as a representation of a generalized and simplified geological model. Main results obtained from this study have demonstrated the following conclusions: (1) consideration of porosity–permeability variations can have significant impacts on the computational simulation solutions of coupled rock deformation, porosity–permeability evolution and pore-fluid flow problems in fluid-saturated porous rocks; (2) different structural deformation regimes can have a significant effect on the mineralization enrichment distributions in ore-forming systems consisting of fluid-saturated porous rocks; (3) there are two favorable mineralization enrichment environments associated with compressional and extensional deformation regimes in ore-forming systems involving permeable fractured zones or faults.