TY - JOUR
T1 - Morphological instabilities of stressed and reactive geological interfaces
AU - Angheluta, Luiza
AU - Mathiesen, Joachim
AU - Misbah, C.
AU - Renard, F.
PY - 2010/6/24
Y1 - 2010/6/24
N2 - Interfaces between contacting rocks of the Earth's crust are shown to be unstable and corrugating and develop roughness at various scales when submitted to nonhydrostatic stress. This instability may occur in various geological settings as long as a coherent deformation of the interface is allowed and the bodies that the interface separates have different material properties (i.e., viscosity, density, or elastic moduli). Relevant examples include fault planes, dissolution interfaces, or grain boundaries. Performing a twodimensional linear stability analysis, we consider two cases: one solid in contact with a viscous layer and two solids separated by a thin viscous layer. In both cases either shear and/or normal loads are imposed on the interface and thermodynamical conditions for the initiation of roughening are established. Applied on several geological systems such as grain contacts and fault planes, we propose that our analysis can explain how complex patterns may emerge at rock-rock interfaces. Finally, we provide an analysis of the evolution of the static friction coefficient along sheared interfaces. The evolution is shown to depend solely on Poisson's ratio of the solid and the ratio of the shear and compressional stresses along the interface.
AB - Interfaces between contacting rocks of the Earth's crust are shown to be unstable and corrugating and develop roughness at various scales when submitted to nonhydrostatic stress. This instability may occur in various geological settings as long as a coherent deformation of the interface is allowed and the bodies that the interface separates have different material properties (i.e., viscosity, density, or elastic moduli). Relevant examples include fault planes, dissolution interfaces, or grain boundaries. Performing a twodimensional linear stability analysis, we consider two cases: one solid in contact with a viscous layer and two solids separated by a thin viscous layer. In both cases either shear and/or normal loads are imposed on the interface and thermodynamical conditions for the initiation of roughening are established. Applied on several geological systems such as grain contacts and fault planes, we propose that our analysis can explain how complex patterns may emerge at rock-rock interfaces. Finally, we provide an analysis of the evolution of the static friction coefficient along sheared interfaces. The evolution is shown to depend solely on Poisson's ratio of the solid and the ratio of the shear and compressional stresses along the interface.
U2 - 10.1029/2009JB006880
DO - 10.1029/2009JB006880
M3 - Journal article
SN - 2169-9003
VL - 115
SP - B06406
JO - Journal of Geophysical Research: Earth Surface
JF - Journal of Geophysical Research: Earth Surface
ER -