The complexity of geological features observed in nature is the result of interactions between various processes, including mechanical deformation, fluid flow, heat transfer and chemical reactions. Those mechanisms have been treated for a long time as separate research areas, but scientists are now increasingly looking at coupled interactions where all feedbacks are involved. This book provides a new framework to account for all geological processes mentioned above and simulate numerically more complex geological scenarios using the finite element method. Continuum Damage Mechanics is a critical element in this work and damage in the host rock is linked to porosity evolution, which in turn affects permeability. This study should be especially useful to geological modellers interested in coupled interactions. It presents a numerical tool to analyse the resulting competition of rates of processes, particularly in the context of mineral and geothermal exploration.