Excess3He in the deep water over the Mid-Atlantic Ridge at 26°N: evidence of hydrothermal activity

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Abstract

We have observed distinct and significant patterns of excess3He in bottom waters over the Mid-Atlantic Ridge in the “TAG hydrothermal field”. The lateral regional gradients are comparable in magnitude to gradients observed in the Galapagos rift, an area of confirmed hydrothermal activity. Together with this, the3He patterns, magnitudes and vertical gradients all indicate on-going and continuous hydrothermal activity.

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