Data for: Temperature-dependent frictional properties of heterogeneous Hikurangi Subduction Zone input sediments, ODP Site 1124
Description
This text file contains the complete experimental dataset. Data for each experiment listed in Table 1 appear as columns of displacement (mm) and coefficient of friction (mu). Acquired raw torque and normal force data were processed to obtain shear stress and normal stress measurements respectively. The externally measured torque was corrected for fluid pressure and shear displacement-dependent friction of the Teflon-coated O-ring seals using calibration values obtained in runs with a dummy sample of carbon-coated PolyEtherEtherKeton with a known sliding friction; seal friction is typically around 0.03 kN (equivalent to ~1.5 MPa shear stress). The contribution of the Molykote-coated confining rings to the measured friction is negligible (see also den Hartog et al., 2012). The applied normal stress was corrected for the stress supported by the internal seals, the level of which is clearly visible during initial loading and was generally around 0.5 kN (equivalent to ~2 MPa normal stress acting on the sample). Repeat experiments (u644 and u713) on sample 181-1124C-44X-7, 4-6 cm (428.34 mbsf), yielded an analytical error of 0.03-0.05 mu. The analytical error is thought to reflect the fact that the second experiment was performed on the last remaining sample powder, which may have had more fine-grained clays (e.g., sample inter-variability), and/or because of variations in sample preparation.