Rheology (from the Greek ρειν, “to flow”) is the study of the properties of materials that determine how they flow in response to applied forces. The quantities that characterize the internal state of a flowing material are the stress (the force per unit area acting on internal surfaces) and the strain rate (the rate at which the flow velocity varies from point to point). The mathematical relation between the two is called the “rheology” of the material. Rheology is a critical issue for numerous industrial and natural processes spanning a huge range of spatial and temporal scales.  Understanding and controlling the rheology of complex fluids is essential for industrial products with hundreds of billions of euros in annual sales, like processed food, cosmetics, paint, polymers, and glass.  It is also essential for predicting the effect of forming processes on the engineering properties of the metallic or ceramic pieces and to optimize the combination of thermal and mechanical processes used in their fabrication. The rheology of rocks is an essential parameter for the dynamics of our planet. On a global scale, the most important evidence for the complex rheology of the silicate Earth is plate tectonics, which corresponds to a highly heterogeneous and localized deformation of the Earth’s surface in response to global mantle convection. Complex rheology is a necessary condition  for producing strain localization. The “Grand Challenge” is to understand how the different factors that determine the rheology of rocks work together to influence large-scale dynamics of our planet. Rheology is also a critical parameter in many fields of Earth Sciences that have a direct societal impact. Estimating earthquakes and tsunami hazard depends essentially on our knowledge of faults rheology. Establishment of safe natural reservoirs for chemical and radioactive waste is contingent on our ability to predict the deformation of these reservoirs and its effect on their sealing capacity over long time spans. Interactions between deformation and fluids are also a fundamental parameter in energy production, both for the extraction of fossil fuels and for the development of clean energy production methods, like geothermal.

CREEP proposes an  interdisciplinary and multiscale approach to study the origin of rheological complexity in Earth and analogous materials and how it controls the dynamics of our planet, including natural and human-induced seismicity, and affects a large range of industrial applications, from energy production and waste storage to production of high-performance glasses.

The primary objectives of CREEP are:

1.  to  advance our understanding of the complex rheology of Earth and industrial materials and its consequences to our planet dynamics, including natural and induced seismicity, to the production of fossil or renewable energy production, or on industrial applications using a fully multidisciplinary approach (mineral physics, petrology, seismology, geodynamics) spanning the whole range of spatial scales involved, from the nanoscale to global mantle dynamics;

2. to train 16 early-stage researchers (ESRs) in state-of-the-art concepts and leading-edge research techniques that are essential to study the rheological behaviour of complex materials and their consequences to a large variety of Earth and industrial processes, while providing them strong career-management skills and solid professional connections;

3. to increase the impact and international visibility of European research by establishing a long-term synergistic partnership among 10 internationally recognized academic research teams in complementary fields of Earth Sciences, one non-profit organization, and 10 industrial partners.