Koselleck
Reinhard-Koselleck Project
Experimental investigations concerning the coupling of reaction progress and permeability
Project description
Interactions between water and rock play an essential role in the geosciences. On the one hand, they regulate the climate-determining mass exchange between the earth's crust and the oceans. On the other hand they influence hydraulic and rock mechanical properties and are therefore of great importance in applied geosciences. In these interactions, volume changes of the solid phases continuously modify the distribution of porosity and permeability in the rock. The rates at which the crucial dissolution and precipitation reactions take place, in turn depend very much on the distribution of porosity and permeability. Little is known about these feedbacks between reaction sequence and pore space distribution, and this has repeatedly emerged as a problem in the assessment and prediction of system behaviour in the geosciences. Here, experimental work is proposed in which the focus is on systematic studies of these feedbacks. Flow experiments are to be carried out at elevated pressures and temperatures on rock bodies with corrosive or supersaturated solutions. The reactions thus initiated modify the geometry of the pore space. These changes are imaged by computer tomography (µ-CT), while time series analyses of the fluid compositions deliver information on the development of thermodynamic and kinetic parameters. The knowledge gained in these experiments will be used to parameterize numerical models for the prediction of coupled flow and mass transport processes.
