Regional Flow Simulation in Fractured Aquifers Using Stress-Dependent Parameters

TL;DR

This paper introduces a stress-dependent model for simulating flow in fractured aquifers, accounting for elastic and statistical fracture parameters, permeability variations, and porosity changes at regional scales.

Contribution

It develops a novel tensorial permeability model based on effective stress, enhancing phenomenological accuracy over classical methods.

Findings

Model successfully simulates stress-dependent permeabilities from lab to field.

Permeability tensors vary in strength and direction with stress.

Allows evaluation of fracture porosity and medium consolidation.

Abstract

A model function relating effective stress to fracture permeability is developed from Hooke's law, implemented in the tensorial form of Darcy's law, and used to evaluate discharge rates and pressure distributions at regional scales. The model takes into account elastic and statistical fracture parameters, and is able to simulate real stress-dependent permeabilities from laboratory to field studies. This modeling approach gains in phenomenology in comparison to the classical ones because the permeability tensors may vary in both strength and principal directions according to effective stresses. Moreover this method allows evaluation of the fracture porosity changes, which are then translated into consolidation of the medium.