oa Numerical Modelling of the Mechanical and Fluid Flow Properties of Fault Zones – Implications for Fault Seal Analysis

Existing fault seal algorithms are based on fault zone composition and fault slip (e.g., shale gouge ratio), or on fault orientations within the contemporary stress field (e.g., slip tendency). In this study, we aim to develop improved fault seal algorithms that account for differences in fault zone composition as well as deformation conditions under which the fault zone developed. The influence of composition and deformation conditions on the fluid flow properties of fault zones is investigated using discrete element simulations and laboratory experiments (cf. companioning paper by Giger et al.) of samples consisting of a low-permeability clay or shale layer, embedded in porous sandstone. A combination of discrete element and finite difference models is used to upscale the results and investigate the evolution of fault zone architecture and fluid flow properties of outcrop-scale faults. The fault seal algorithms are tested in a case study using finite element models of reservoir-scale faults.