10Be in the Atlantic ocean, a transect at 25° N

Abstract The 10 Be concentration of the water column was measured on 5 profiles on a transect across the Atlantic at ≈ 25° N. In the deep water the profiles display a 10 Be concentration of 1920 atoms g near the Mid-Atlantic Ridge, 1300 atoms g in the Western Basin, and 1300–1670 atoms g in the Eastern Basin, From this, the residence time of 10 Be in the deep water can be calculated to 380–560 Ma. This agrees well with earlier estimates from the flux into sediments from the Eastern Basin. For the surface water, the residence time yields to 10–13 a.