Reactive fluid migration in stressed rocks

Understanding fluid flow in porous media is relevant for a whole range of applications both within and outside the Earth Sciences. In this project we aim to ivenstigate the migration of reactive fluids in rocks that are under significant differential stress even before fluid migration starts.

Figure: Reactive fluid migration in stressed rocks. The dark layer is offset by a number of faults caused by tectonic stress. Fluids passing through these faults have reacted with the original rock (dunite) to produce serpentinite (light color). The reaction causes local swelling and closure of the flow paths.

Figure: Reactive fluid migration in stressed rocks. The dark layer is offset by a number of faults caused by tectonic stress. Fluids passing through these faults have reacted with the original rock (dunite) to produce serpentinite (light color). The reaction causes local swelling and closure of the flow paths.

About the research

Understanding fluid flow in porous media is relevant for a whole range of applications both within and outside the Earth Sciences. It has been described by quantitative models for more than 150 years (D’Arcy, 1856). In the simplest models, the porous media is not affected by the fluid flow and the fluid-solid interface does not change with time.  In the more general case that applies to most natural (geological) situation, the migrating fluid interacts with the surrounding solid matrix, both chemically and mechanically.

Dissolution and precipitation processes during flow change the geometry of the fluid-solid interface. Stresses associated with fluid pressure gradients, with gravitational forces and even with growth of new minerals in the pore space often lead to deformation of the fluid-solid interface.

The research, focuses on the migration of reactive fluids in rocks that are under significant differential stress even before fluid migration starts. This is a very common situation in the Earth’s crust even away from plate tectonic boundaries, but has hitherto received limited attention by the geophysical community. So far, neither numerical models, nor any experiments have been performed on reactive fluid migration in pre-stressed rocks.

Cooperation

Published Nov. 5, 2015 12:13 PM - Last modified Dec. 11, 2015 2:30 PM