Articles scientifiques
F.E. Grousset, P.E. Biscaye, A. Zindler, J. Prospero, and R. Chester (1988)
Neodymium isotopes as tracers in marine sediments and aerosols: North Atlantic
Earth and Planetary Science Letters, 87(4):367-378.
Nd and Sm concentrations and Nd isotopic compositions were measured on the detrital fraction of deep-sea surface sediments and on aerosols sampled over the North Atlantic and Mediterranean Sea. The data, expressed as[epsilon]Nd(0) and as model ages, ranged from-14.5 [epsilon]Nd(0) +4.9 and from 0.01 to 2.21 Ga, respectively. Two areas where the sediments contain relatively less radiogenic Nd are to the west off North Africa and eastward of the Canadian shield. This distribution is consistent with other tracers in suggesting that a significant fraction of the sediments are derived from aeolian material transported by major wind systems. Saharan dust transported in the equatorial trade winds belt, and North American soil material transported in the latitudes of the westerlies. Between these aeolian-dominated belts, along an axis from the Azores to Gibraltar and the Mediterranean, lies a zone of more radiogenic[epsilon]Nd(0) values in sediments and aerosols influenced by the recent volcanism of this region.br/Previously reported distributions of Nd isotopes in bottom-formed iron-manganese crusts and coatings, are similar to distributions of Nd isotope values in detrital sediments and aerosols. This suggests that the detrital fraction has undergone partial dissolution and desorption in the water column and/or in the pore waters of near-surface sediments, and that a significant proportion of Nd in the authigenic ferromanganese phases is derived from this source, and may therefore not represent strictly dissolved seawater Nd isotope ratios, useful as watermass tracers
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