AL-26 IN SEAWATER AND AL-26 BE-10 AS PALEO-FLUX TRACER/

Measurements of water-column Al-26/Al-27 ratios above 850 m depth in t he Pacific yield values in the range 10(-13)-10(-14), translating into Al-26 concentrations of 20-200 atoms kg(-1). The atomic ratio of Al-2 6/Be-10 in surface ocean is close to 1x10(-4), at least an order lower than the atmospheric production ratio. Surface-ocean particulate remo val of Al is about 30 times more rapid than that of Be. The results of this first set of data on Al-26 in seawater also suggest that the sou rce of Al-26 in the sea is dominated by spallation of Ar in the atmosp here (as opposed to eolian and cosmic-dust inputs) and that the ratio Al-26/Be-10 in marine sediments can be potentially used to decipher pa st variations of oceanic particle flux, hence biologic productivity.