(Table 1) Calcium and magnesium in porewater at DSDP Hole 94-608

The suggestion that nuclear waste material might be buried within the sediments of the deep ocean has increased interest in possible ways that vertical pore-water movement might be detected and measured. A heat-flow station (Discovery 10335) previously occupied near Kings Trough indicated nonlinear temperature-depth profiles in the surficial sediments, which could be interpreted in terms of a very high upward pore-water velocity. The calcium and magnesium pore-water profiles at Site 608, however, prove to be unusually linear and show a strong inverse correlation with each other. In these circumstances it is very unlikely that vertical pore-water movements have occurred, and the application of a simple model indicates that, given the assumptions of this model, the vertical pore-water advection velocity has been zero ± 0.006 cm yr**-1. for a substantial fraction of the recent sedimentological history of this area.