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doi:10.2204/iodp.proc.319.203.2015

Results

Particle size distribution curves were created for all 46 samples. Table T1 gives the sand, silt, and clay percentages calculated using the hydrometer analysis. Figures F2 and F3 show an example data sheet and plot for our hydrometer analysis (see GRAINSIZ in “Supplementary material” for similar graphs for each sample).

Figure F4 shows a particle distribution graph showing depth versus grain density and weight percent clay. Because we did not measure the density of the actual grain size samples, we determined an error resulting from using MAD density values from depths that are close to the depth of the grain size samples. To test the error in our grain density, we present the data using three constant grain density values. We calculated all grain size distributions to have a grain density of 2.7 g/cm³ as an average specific gravity. We then altered all 46 samples to have a specific gravity of 2.6 and 2.8. The fraction of clay present varied only ±0.8% compared to the grain size distribution with a specific gravity of 2.7. This demonstrates that variation in grain density over a reasonable range has a small effect on the interpreted grain size distribution.

Using the ternary diagram in Figure F5, we plot the sand, silt, and clay percentages for all 46 samples. Nearly all samples are within the clayey-silt field with a few scattered sandy-silts, silty-sands, and sands. The samples are more clay rich in the uppermost section, as seen in the particle distribution graph (Fig. F6).

The downcore profile for sand, silt, and clay against gamma ray, spontaneous potential, resistivity, lithology, and core information is shown in Figure F6.

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