Hydrothermal exploration of the Fonualei Rift and Spreading Center and the Northeast Lau Spreading Center
Hydrothermal exploration of the Fonualei Rift and Spreading Center and the Northeast Lau Spreading Center
复制标题
Fonualei 裂谷和扩张中心以及东北 Lau 扩张中心的热液勘探
DOI：
10.1029/2006gc001324
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发表时间：
2006
期刊：
影响因子：
3.7
通讯作者：
C. Langmuir
中科院分区：
文献类型：
--
作者：
C. German;E. Baker;D. Connelly;J. Lupton;J. Resing;R. Prien;S. Walker;H. Edmonds;C. Langmuir
我们报道了沿着东北刘盆地的两个弧后扩张中心：丰努阿雷裂谷和扩张中心(FRSC)和东北刘扩张中心(NELSC)活动的热水喷发的证据。这里所研究的海脊段尤其值得注意，因为它是水中热液羽流(1500-2000米深)的潜在来源，该热液羽流横跨西南太平洋延伸超过2000公里，从靠近刘盆地最东北端的表观起源分散开来。我们的结果表明，至少存在四个新的热液羽状源，三个沿着FRSC，一个在NELSC上，后者位于先前发现的西南太平洋区域尺度羽流的最大值150公里范围内。然而，我们所确定的最南端FRSC羽流中的TDFe和TDMn浓度仅达到19和13nmol/L，同一羽流中溶解的3He异常也很小，无论是相对于西南太平洋羽流还是与当地背景都是如此，这表明3He在整个刘盆地水柱中都有广泛的富集。我们的结果显示，东北刘盆地没有任何一个主要的热液来源的证据。相反，我们得出结论认为，区域尺度的西南太平洋热液羽流很可能是整个地形受限的LAU盆地通过其最北北角排放的累积热液输出的结果。
We report evidence for active hydrothermal venting along two back‐arc spreading centers of the NE Lau Basin: the Fonualei Rift and Spreading Center (FRSC) and the Northeast Lau Spreading Center (NELSC). The ridge segments investigated here are of particular interest as the potential source of a mid‐water hydrothermal plume (1500–2000 m depth) which extends more than 2000 km across the SW Pacific Ocean dispersing away from an apparent origin close to the most northeastern limits of the Lau Basin. Our results indicate the presence of at least four new hydrothermal plume sources, three along the FRSC and one on the NELSC, the latter situated within 150 km of the maximum for the previously identified SW Pacific regional‐scale plume. However, TDFe and TDMn concentrations in the southernmost FRSC plume that we have identified only reach values of 19 and 13 nmol/L and dissolved 3He anomalies in the same plume are also small, both in relation to the SW Pacific plume and to local background, which shows evidence for extensive 3He enrichment throughout the entire Lau Basin water column. Our results reveal no evidence for a single major point hydrothermal source anywhere in the NE Lau Basin. Instead, we conclude that the regional‐scale SW Pacific hydrothermal plume most probably results from the cumulative hydrothermal output of the entire topographically restricted Lau Basin, discharging via its NE‐most corner.