Characterization of major discontinuities from borehole cores of the black consolidated marl formation of Draix (French Alps)

Amélie Neuville (1) , Renaud Toussaint (2, 3) , Jean Schmittbuhl (4) , Daniel Koehn (5) , Jens Oliver Schwarz (5)

1 IPGS - Institut de physique du globe de Strasbourg
2 IPGS-GE - Géophysique expérimentale (IPGS)
3 Centre for Advanced Study at the Norwegian Academy of Science and Letters
4 IPGS-Sismologie - Sismologie (IPGS)
5 Tectonophysics

A quantitative description of rock discontinuities present in subsurface cores that were drilled (down to 20 m) in the marls of the Laval and Moulin catchments near Draix (France) is presented. Three kinds of discontinuities are studied: those fully open, those open but filled with clay rich material and those sealed with calcite. With a laser profiler, the topography of facing sides of typical discontinuities was measured with a normal resolution of 1 µm. The probability distribution of the elevation of each surface are obtained and shown to be normal. Possible self-affine scaling invariance of the topography were explored. The mineralogical content of an interface between the marl bulk and the embedded calcite vein is also investigated using X-ray computed tomography. Implication of this study for water transport in such discontinuities is addressed in a companion paper in the same issue.

Domaines: Sciences de la Terre; Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Amélie Neuville, Renaud Toussaint, Jean Schmittbuhl, Daniel Koehn, Jens Oliver Schwarz. Characterization of major discontinuities from borehole cores of the black consolidated marl formation of Draix (French Alps). Hydrological Processes, 2012, pp.7984. ⟨10.1002/hyp.7984⟩. ⟨hal-00701969⟩