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doi:10.2204/iodp.proc.331.106.2011

Physical properties

Physical property measurements were made at Site C0016 to nondestructively characterize lithological units and states of sediment consolidation. Cores collected from this site were all composed of hard rock. Because the core was collected in a 4 inch liner, the multisensor core logger for whole-round samples (MSCL-W) measurement of P-wave velocity was not conducted.

Density and porosity

Bulk density at Site C0016 was determined from both gamma ray attenuation (GRA) measurements on whole cores (with the MSCL-W) and moisture and density (MAD) measurements on discrete samples (see “Physical properties” in Expedition 331 Scientists, 2011b). A total of four discrete samples were analyzed for MAD from Hole C0016B. Wet bulk density ranges from 2.4 to 2.9 g/cm³ (Fig. F8). As at previous sites, GRA-derived density is somewhat lower (~2.0 g/cm³) and exhibits more scatter (Fig. F8). Bulk density near the seafloor (0.3 mbsf) is 2.8 g/cm³. It decreases to 2.4 g/cm³ at 9 mbsf and then increases again to 2.8–2.9 g/cm³ at 27–28 mbsf. Grain density was calculated from discrete MAD measurements and ranges from ~2.8 to 3.0 g/cm³ (Fig. F8). Porosity was calculated from MAD measurements (Fig. F9). The water content in these rocks is quite low, between 3% and 10%, except at 9 mbsf where the porosity is higher (22%)

Density and porosity results are consistent with the presence of silicified rocks.

Electrical resistivity (formation factor)

Formation factor was not measured at Site C0016 because the resistivity electrode could not penetrate the lithified core material.

Discrete P-wave velocity and anisotropy measurements

P-wave velocity and relative anisotropy were measured on two sample polyhedrons collected from near the bottom of Hole C0016B. P-wave velocities at 27–28 mbsf range from 4000 to 4900 m/s (Fig. F10).

Thermal conductivity

Thermal conductivity was measured on split cores using the half-space probe method. A total of four measurements were made from Hole C0016B. Values range from a low of ~4 W/(m·K) at 9 and 27.1 mbsf to high values of 7.4 and 10.2 W/(m·K) at 0.3 and 28 mbsf, respectively (Fig. F11). Thermal conductivity is loosely and inversely correlated with porosity. As porosity decreases, thermal conductivity increases as water is forced from void spaces, because the thermal conductivity of grains is greater than that of water.

MSCL-I and MSCL-C imaging

MSCL-derived core images and color analyses are presented in the visual core descriptions (VCDs).

MSCL-W derived electrical resistivity

MSCL-W-based resistivity data are sparse. At 1 mbsf resistivity ranges from 1 to ~50 Ωm; at ~27 mbsf the maximum resistivity is higher, ~110 Ωm (Fig. F12).

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