The characterisation of linked physical properties such as elasticity, strength and permeability from outcrop to crustal scales is complicated by heterogeneity, fabric anisotropy and microcracking (“intact rock”) and by geological structure and inherited fracturing (“rock mass”), especially in complex geodynamic settings. Rocks can behave as continuous or discontinuous media depending on the scale of consideration and the occurrence of discrete structures (e.g. fault zones). Moreover, rock properties and inherited geological features constrain mechanical damage processes resulting in rock mass weakening, altered permeability and hydro-mechanical coupling between rock and fluids, development of brittle shear zones, and time-dependent rock mass behavior (creep).
Despite major experimental, theoretical and modelling advances, a remaining future goal is to develop meaningful, testable methods and models that allow us to quantify the relationships between fabric and fractures related to the geomechanical behavior of rocks on different scales and in different environmental conditions (P, T, fluids). This is critical in order to unravel the complex evolution and dynamics of the Earth’s crust, and develop predictive capabilities for geohazard and energy applications.
In this session we will bring together researchers from different communities, working on problems related to quantifying the hydro-geomechanical properties and behavior of rock masses considered either as continua or discontinua. We will explore their geological controls from the micro- to macro-scale, in a range of crustal environments and geological (understanding gas and magma movement and hydrothermal systems at volcanoes or fluid pressure and damage evolution within fault zones) and geohazard applications (e.g. rock slope instability and related geomorphic impacts, fractured reservoir exploitation, subsidence due to drainage, induced seismicity), using experimental and numerical approaches in the laboratory and the field. We especially welcome studies that adopt novel approaches and combined methodologies.