Geochemical investigations of beryllium will be continued that include studies of Be isotopes in aerosols, in rain, in ocean, river and estuarine waters and their particulate matter, and in marine deposits. Particular attention will be paid to: determining the distribution and degree of isotopic homogenization of 10Be/9Be in the deep ocean, evaluating the 7Be/10Be ratio as a tracer of oceanic process, exploring the use of pore water 9Be as an normalization parameter for the 10Be geochronometry, and studying non-steady state elemental removal in surface ocean with multiple tracers of 7Be/10Be and U/Th series isotopes. Planned field collections include water column 10Be/9Be study in the S. Atlantic, atmospheric 7Be/10Be study in Los Angeles, and Be and U-Th series isotope study in the San Pedro Basin off Southern California. This project aims at gaining an understanding of the geochemical behavior and distribution of the isotopes of beryllium (10Be, 9Be, and 7Be) in the ocean-atmospheric system. Such an understanding will provide insight and facilitate the use of these isotopes as tracers for a number of oceanographic and geophysical problems such as geochronology of marine deposits for the past 15 million years, ocean mixing, particulate flux, trace element scavenging, variation of cosmic-ray and geomagnetic field intensity.