Enrichments in Hg, Cd, As, and Sb in recent sediments of Azores-Iceland Ridge

F. Grousset1, O. Donard2
1Laboratoire Associe au C.N.R.S. n° 197-Université Bordeaux I, Talence Cedex, France
2Département de Géologie et Océanographie, Université Bordeaux I, Talence Cedex, France

Tóm tắt

Mercury, cadmium, arsenic, and antimony were analyzed in cores sampled on the Azores-Iceland Ridge. High values of 780 μg · kg−1 for Hg, 1.7 μg · g−1 for Cd, 87 μg · g−1 for As, and 8.1 μg · g−1 for Sb occur in the rift valley and transform faults. These enrichments, strictly linked to the ridge, could not have an allochtonous origin. A local hydrogenous flux may explain this phenomenon. These metallic enrichments may be connected to a hydrothermal activity extended between 43° N and 47° N.

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Tài liệu tham khảo

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