Neodymium isotopes and concentrations in Caribbean seawater: Tracing water mass mixing and continental input in a semi-enclosed ocean basin
Neodymium isotopes and concentrations in Caribbean seawater: Tracing water mass mixing and continental input in a semi-enclosed ocean basin
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加勒比海水中的钕同位素和浓度：追踪半封闭洋盆中的水团混合和大陆输入
DOI：
10.1016/j.epsl.2014.09.011
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发表时间：
2014
影响因子：
5.3
通讯作者：
Floegel
中科院分区：
文献类型：
--
作者：
Osborne;Hathorne;Floegel
我们提出了第一个完整的水柱Nd同位素（ε Nd）和浓度数据加勒比海，以及站靠近奥里诺科河口和佛罗里达海峡。通过圭亚那海流流入加勒比海东南部的地表流的特征是ε Nd信号为− 10.9，这是奥里诺科河提供的相对非放射性ε Nd信号（− 13.6）与亚马逊河的贡献（ε-10）混合的结果。尽管靠近陆地，但加勒比海内的次表层和中层沃茨基本上保留了其大西洋源水质量的ε Nd特征。相比之下，加勒比的深水沃茨显示出比流入的北大西洋深水（UNADW）多至少3个ε Nd单位的ε Nd特征。ε Nd从− 13变化到− 9.7可以解释为通过陆地风化输入向加勒比海深处添加了放射成因Nd。然而，为了平衡ε Nd的这种大的变化，同时适度增加Nd浓度，Nd也必须从盆地内的海水中去除。有人建议，在加勒比深海沃茨的长期停留时间允许海水与下沉颗粒和海底沉积物的显着相互作用，从而导致更多的放射性值。这些研究结果的使用ε Nd作为一个代理的古循环在受限制的盆地，其中的深沃茨的停留时间很长的影响。
We present the first full water column Nd isotope (ε Nd) and concentration data for Caribbean seawater, as well as for stations close to the Orinoco River mouth and in the Florida Straits. The surface inflow into the southeastern Caribbean via the Guyana Current is characterized by an ε Nd signature of− 10.9, which is a consequence of the mixing of relatively unradiogenic ε Nd signatures (− 13.6) supplied by the Orinoco River with contributions from the Amazon River (∼− 10). Despite the proximity to land, sub-surface and intermediate waters within the Caribbean largely retain the ε Nd signatures of their source water masses in the Atlantic. In contrast, the deep waters of the Caribbean show ε Nd signatures at least 3 ε Nd units more radiogenic than the inflowing Upper North Atlantic Deep Water (UNADW). A ε Nd shift from− 13 to− 9.7 can be explained by addition of radiogenic Nd to the deep Caribbean through weathering inputs from land. However, in order to balance such large shifts in ε Nd with at the same time modest increases in Nd concentrations, Nd must also be removed from seawater within the basin. It is suggested that the long residence time of deep waters in the Caribbean allows significant interaction of seawater with sinking particles and seafloor sediments resulting in more radiogenic values. These findings have implications for the use of ε Nd as a proxy for paleocirculation in restricted basins, in which the residence times of the deep waters are long.
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影响因子：
5
作者：
S. Kraft;M. Frank;E. Hathorne;S. Weldeab
通讯作者：
S. Kraft;M. Frank;E. Hathorne;S. Weldeab
巴芬湾水的钕同位素研究：来自非常古老地体的稀土元素来源
影响因子：
5.3
作者：
M. C. Stordal;G. Wasserburg
通讯作者：
G. Wasserburg
影响因子：
5.3
作者：
T. Stichel;M. Frank;J. Rickli;B. Haley
通讯作者：
T. Stichel;M. Frank;J. Rickli;B. Haley
DOI：
--
发表时间：
2005
期刊：
影响因子：
--
作者：
R. Lumpkin;S. Garzoli
通讯作者：
S. Garzoli
关于佛罗里达洋流的来源
影响因子：
4.9
作者：
W. Schmitz;P. Richardson
通讯作者：
P. Richardson