10. Data Report: Permeability, Compressibility, and Friction Coefficient Measurements under Confining Pressure and Strain, Leg 190, Nankai Trough1

Sylvain Bourlange,2, 3 Laurence Jouniaux,2 and Pierre Henry2, 4


Permeability measured on three samples in a triaxial cell under effective confining pressure from 0.2 to 2.5 MPa ranges from 10–18 to 10–19 m2. Overall, results indicate that permeability decreases with effective confining pressure up to 1.5 MPa; however, measurements at low effective pressure are too dispersed to yield a precise general relationship between permeability and pressure. When the effective pressure is increased from 1.5 to 2.5 MPa, permeability is roughly constant (~1–4 x 10–19 m2). Samples deformed in the triaxial cell developed slickenlined fractures, and permeability measurements were performed before and after failure. A permeability increase is observed when the sample fails under low effective confining pressure (0.2 MPa), but not under effective pressure corresponding to the overburden stress. Under isotropic stress conditions, permeability decrease related to fracture closure occurs at a relatively high effective pressure of ~1.5 MPa. Coefficients of friction on the fractures formed in the triaxial cell are ~0.4.

1Bourlange, S., Jouniaux, L., and Henry, P., 2004. Data report: Permeability, compressibility, and friction coefficient measurements under confining pressure and strain, Leg 190, Nankai Trough. In Mikada, H., Moore, G.F., Taira, A., Becker, K., Moore, J.C., and Klaus, A. (Eds.), Proc. ODP, Sci. Results, 190/196, 1–16 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/ publications/190196SR/VOLUME/ CHAPTERS/215.PDF>. [Cited YYYY-MM-DD]

2Laboratoire de Geologie, Ecole Normale Superieure UMR 8538, 24 rue Lhomond, 75231 Paris Cedex 05, France. Correspondence author: bourlang@geologie.ens.fr

3Present address: LIAD–ENSG, Rue du doyen Marcel Roubault, BP 40, 54500 Vandoeuvre, France.

4Present address: Chaire de Geodynamique, College de France, Europole de l’Arbois, BP 80, 13545 Aix en Provence Cedex 04, France.

Initial receipt: 29 July 2003
Acceptance: 14 January 2004
Web publication: 16 July 2004
Ms 190SR-215