This report presents a summary of grain-size data for samples of hemipelagic sediment from Sites 1173, 1174, 1175, and 1177. These data consist of the weight percents of sand, silt, and clay, mean grain size, and standard. We also show the values of porosity, bulk density, void ratio, and water content as measured shipboard for nearby sample intervals. These data provide useful information for physical properties and geotechnical experiments, especially those which will attempt to examine the lithologic controls on the mechanical properties or fluid-sediment interactions.
At Sites 1173 and 1174, bulk density appears to increase with weight percent clay, whereas porosity, void ratio, and water content appear to decrease with weight percent clay. These relations, however, are strongly influenced by a combination of facies changes and increasing compaction with depth. Thus, the true effect of grain size as a primary control on physical properties has been masked by spatial and temporal variations in compaction. Correlations between grain-size parameters and index properties are even weaker at Site 1177. This may be due to differences in compaction within the heterogeneous lithologies of the lower Shikoku Basin turbidite facies.
New laboratory procedures have been developed for using the Spectrex laser particle counter with fine-grained sediment. We used an empirical correlation with pipette analysis to convert laser particle counter results to weight percent of spherical equivalent settling.