Data report: permeability of mud(stone) samples from IODP Sites C0006 and C0007, Nankai Trough Seismogenic Zone Experiment

Abstract

In this study, we executed constant-flow permeability tests in the horizontal (cross-core) and vertical (along-core) directions using 11 whole-round core specimens of mud(stone) from Integrated Ocean Drilling Program Nankai Trough Sites C0006 and C0007. The samples came from ~34 to 564 meters below seafloor and include lithostratigraphic Units II (accreted trench wedge) and III (upper Shikoku Basin facies). Effective isotropic confining stress during the tests was set at 0.55 MPa (80 psi). At Site C0006, the highest value of vertical hydraulic conductivity (K v) is 1.60 × 10-6 cm/s and the lowest value of vertical hydraulic conductivity is 2.63 × 10-10 cm/s. The highest value of horizontal hydraulic conductivity (K h) is 2.07 × 10-6 cm/s, and the lowest value of horizontal hydraulic conductivity is 3.25 × 10-10 cm/s. The average ratio of horizontal to vertical intrinsic permeability (k h /k v) is 4.27. At Site C0007, the highest value of vertical hydraulic conductivity is 1.24 × 10-9 cm/s and the lowest value of vertical hydraulic conductivity is 9.54 × 10-10 cm/s. Horizontal hydraulic conductivity reaches a maximum of 1.15 × 10-9 cm/s, and the lowest value of horizontal hydraulic conductivity is 8.09 × 10-10 cm/s. The average ratio k h /k v is 0.93 for specimens at Site C0007. Environmental scanning electron microscopy was used to evaluate the relation between sediment microstructure and anisotropy of permeability. The index of orientation does not vary significantly and shows a weak correlation with k h /k v values.

Apparent overconsolidation of mudstones in the Kumano Basin of southwest Japan: Implications for fluid pressure and fluid flow within a forearc setting

“…[32] Siliciclastic mudstones and siltstones exhibit a very wide range of permeabilities, from 10 À23 to 10 À14 m 2 [e.g., Neuzil, 1994]; that variability reflects differences in porosity, grain-size distribution, clay content, and pore-size distribution [Bennett et al, 1989;Dewhurst et al, 1998Dewhurst et al, , 1999Yang and Aplin, 2007]. The permeability values reported here are consistent with the results of Gamage et al [2011] from the Nankai Trough ( Figure 6), as well as the "global" permeability-porosity envelope established for mudstones by Neuzil [1994] (see also Dugan and Daigle [2011]; Rowe et al, [2011]; Ekinci et al, [2011];and Yue et al [2012]). The differences in permeability among our specimens are relatively small.…”

“…The permeability values reported here are consistent with the results of Gamage et al . [] from the Nankai Trough (Figure ), as well as the “global” permeability‐porosity envelope established for mudstones by Neuzil [] (see also Dugan and Daigle []; Rowe et al ., []; Ekinci et al ., []; Saffer et al ., []; and Yue et al . []).…”

Data report: permeability of sediments from Sites C0011 and C0012, NanTroSEIZE Stage 2: subduction inputs

“…These data help define the permeability behavior at Site C0011 from 366.76 to 687.15 meters below seafloor (mbsf) and at Site C0012 from 115.44 to 473.11 mbsf. These results complement other permeability analyses within NanTroSEIZE (Boutt et al, 2012;Dugan and Daigle, 2011;Ekinci et al, 2011;Guo et al, 2011;Hüpers and Kopf, 2012;Ikari et al, 2009;Reuschle, 2011;Rowe et al, 2011;Saffer et al, 2011;Yue et al, 2012). Flow properties studies can be coupled with grain-size and sedimentological studies (e.g., Kopf et al, 2011;Guo and Underwood, 2012) to help define the relation between lithology and permeability (e.g., Schneider et al, 2011).…”

Apparent overconsolidation of mudstones in the Kumano Basin of southwest Japan: Implications for fluid pressure and fluid flow within a forearc setting

“…[32] Siliciclastic mudstones and siltstones exhibit a very wide range of permeabilities, from 10 À23 to 10 À14 m 2 [e.g., Neuzil, 1994]; that variability reflects differences in porosity, grain-size distribution, clay content, and pore-size distribution [Bennett et al, 1989;Dewhurst et al, 1998Dewhurst et al, , 1999Yang and Aplin, 2007]. The permeability values reported here are consistent with the results of Gamage et al [2011] from the Nankai Trough ( Figure 6), as well as the "global" permeability-porosity envelope established for mudstones by Neuzil [1994] (see also Dugan and Daigle [2011]; Rowe et al, [2011]; Ekinci et al, [2011]; ; and Yue et al…”