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doi:10.2204/iodp.proc.308.205.2008

Sample preparation (Penn State)

Samples were prepared differently at each university, with prehydrometer analysis sand content obtained only at Penn State using a wet-sieve analysis (sieve-hydrometer method). Samples were first manually disaggregated and placed in a drying oven at 55°C for at least 16 h before recording dry masses. Dried samples were mixed with 5 g of dispersing agent (sodium hexametaphosphate) and ~200 mL of deionized water and tempered for another 24–48 h. The mixture was further disaggregated for 2 min using the ASTM-recommended Hamilton-Beach malt mixer (ASTM D422-63; ASTM International 2003).

To measure sand content of samples, the slurry was washed with deionized water through a 62.5 µm sieve and the retained portion was dried and weighed. This process provided the percentage of sand by weight for each sample processed at Penn State.

The remaining fine-grained slurry was poured into a 1000 mL plastic cylinder and filled with deionized water to create a solution of 1000 mL. We generally prepared 8–16 cylinders before initiating the hydrometer analysis. One cylinder containing only distilled water and 5 g of dispersing agent was also prepared so that reference hydrometer readings could be made and then used to make water density corrections (as described below). A total of 311 samples were analyzed at Penn State (Tables T1, T2). In addition, seven of the samples taken from the remnants of whole-core samples were prepared for reproducibility experiments, the results of which we discuss below.

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