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Research on the Atlantic Ocean off of Africa's Cape Blanc indicates that the U(K')(37) alkenone is not biased toward a higher value during oxic diagenesis. Data were obtained from sediment traps at a 730 m depth from 1990 to 1991, and 2195-3562 m depths from 1988-1991. All fluxes of alkenones demonstrated significant interannual variations with no predictable seasonality.

The article reports findings from a current meter mooring in the Ombai Strait during 1996. The Strait is a deep connection between the Indian and Pacific Oceans. While the upper 200m mean currents were approximately five times higher than those below, the wide and deep strait section promotes a pronounced deep transport.

A study was conducted to analyze lithogenic particle flux and grain size distributions from sediment trap deployments to determine short-term differences in flux and transport of lithogenic matter off northwest Africa. Results indicated a dominant change of dust transport in the trade winds during winter/spring and transport in the Saharan Air Layer at the Cape Verde site. Off Cape Blanc, there was a fast and mostly undisturbed downward transport of particulate matter.

The suspended sediment concentration and benthic flows near the submarine and the Bear Island Fan were studied to determine the feasibility of sediment transport and erosion. The findings provided strong evidence that the Norwegian Sea is a region of energetic current activity where flow speeds reach a maximum value of 50 cm/s. Relatively quiescent flow occurs from summer until autumn, while strongest flow happens between December and early June.

Evidence suggests that fine-grained particles suspended in oceanic waters near the continental shelf concentrate in clouds at levels where there are sharp temperature differences. It is suggested that the existence of such clouds may limit the transport rate of particles, which is moderated by the fingering convection process that occurs at the interface between warm, particle-laden water and cold, fresh water. Details of an experiment designed to investigate the fingering convection process are presented.

The in situ settling speeds of marine snow aggregates in the central Black Sea and the coastal northern Gulf of Mexico are measured using the Marine Aggregate Settling Collector and Observation Tower. Results show that the average settling speeds of marine aggregates in the Black Sea and Gulf of Mexico are 11.7 m/d and 33.8 m/d, respectively for all size classes. No correlation was observed between settling speed and equivalent spherical diameter of aggregates.

Particle-settling through a diffusive-type thermohaline system in the ocean is studied. Results show that the number of suspended particles in a convecting layer decreases exponentially with time, with a decay rate equal to the quotient of the settling velocity and layer depth. The rate of sedimentation also approaches the rate in a non-convecting fluid as the number of layers in the staircase increase.

The natural isotope [super 234]Th is used in a survey of particle transport and exchange processes at the sediment-water interface in the Benguela upwelling area. Three models are presented explaining the [super 234]Th depletion of the bottom nepheloid layer (BNL) and [super 234]Th excess of the surface sediment that are observed.

The power law depth dependence of particulate organic carbon (POC) flux is estimated from sediment-trap data set compiled by Berelson. Results reveal that the variability of the exponent in the power law is only a small contributor to the POC flux variance in the sediment trap data set and the best estimate for the exponent applicable to all stations is 0.70 plusmn 0.08.

A study was conducted to analyze the sensitivity of the computed sinking flux of (super 234)Th in the central equatorial Pacific to physical processes and scavenging mechanism. A meridional and vertical advection and diffusion field was imposed on a dissolved and particulate (super 234)Th cycle. Results indicated that (super 234)Th deficiencies near the equator were significantly influenced by the vertical advection and horizontal diffusion.