Interstitial water studies on small core samples, Deep Sea Drilling Project, Leg 3

Abstract

Eleven samples of fluids which had been squeezed on board ship, and four, packaged sediment samples were received in our laboratories. As in Leg 2, the volumes of fluid available were scanty and did not permit multiple determinations of constituents in many of the samples; in Hole 21 the fluid available sufficed only for refractometer readings (a few tenths of a milliliter). Therefore, analytical scatter is again responsible for partially obscuring variations (and constancy) in the conservative constituents such as sodium. However, on the whole the results confirm the features which appeared in Legs 1 and 2. Central oceanic sediments display a remarkable constancy in total salinity, chlorinity and sodium concentration to the greatest depths and ages yet penetrated in the project drillings. Variations attributable to postburial reactions do occur in the remaining major ions, but they usually show little systematic trend with depth--with the exception of potassium, which will be discussed later. Methods remain similar to those employed for Leg 2; the detailed techniques are now being prepared for submission, but a brief description may be obtained from the previous Leg reports (Manheim and Sayles, 1969; Chan and Manheim, 1970). Results from four unsqueezed samples are not complete and, therefore, do not appear here.