Controls on the distribution of rare earth elements in deep-sea sediments in the North Atlantic Ocean
Controls on the distribution of rare earth elements in deep-sea sediments in the North Atlantic Ocean
复制标题
DOI：
10.1016/j.oregeorev.2016.09.036
复制
发表时间：
2017-07-01
影响因子：
3.3
通讯作者：
Connelly, Douglas
中科院分区：
文献类型：
--
作者：
Menendez, Amaya;James, Rachael H.;Connelly, Douglas
深海沉积物可能含有相对高浓度的稀土元素和钇，人们越来越有兴趣将其开发作为陆地稀土元素资源的替代品。为了了解导致REY在深海沉积物中富集的过程，我们对从大西洋中回收的沉积物进行了详细的地球化学研究，该研究在沿着类似于24 ° N的横断面上进行，其中包括深纳雷斯深海平原以及加那利和北美盆地。重REY（Sigma REY）的总浓度范围为7.99至513 ppm，重REY（Eu-Lu）的总浓度范围为0.993至56.3 ppm。REY浓度最高的缓慢积累的远洋红粘土，特别是在样品中含有铁锰微结节。因子分析结果表明，含氢铁锰氧化物是红粘土中REY的主要载体相。单个微结节的原位分析证实它们具有高REY（高达3620 ppm）。与具有成岩来源的微结节相比，具有氢源的微结节中的Sigma REY浓度较高，其特征是Fe/Mn较高。北大西洋深海沉积物中的Sigma REY含量比太平洋深海沉积物低4倍。我们计算得出，提取全球每年REY需求量的10%所需的海底面积约为100 km（2），假设去除上层1 m的沉积物。(C)© 2016 Elsevier B. V.版权所有。
Deep-sea sediments can contain relatively high concentrations of rare earth elements and yttrium (REY), with a growing interest in their exploitation as an alternative to land-based REY resources. To understand the processes that lead to enrichment of the REY in deep-sea sediments, we have undertaken a detailed geochemical study of sediments recovered from the Atlantic Ocean, on a transect along similar to 24 degrees N that includes the deep Nares Abyssal Plain and the Canary and North America Basins.Total REY concentrations (Sigma REY) range from 7.99 to 513 ppm, and total concentrations of the heavy REY (Eu-Lu) range from 0.993 to 56.3 ppm. REY concentrations are highest in slowly accumulating pelagic red clays, especially in samples that contain ferromanganese micronodules. Factor analysis reveals that hydrogenous Fe-and Mn(oxyhydr)oxides are the primary REY carrier phase in the red clays. In situ analysis of individual micronodules confirms that they have high REY (up to 3620 ppm). Sigma REY concentrations are higher in micronodules that have a hydrogenous source, characterised by higher Fe/Mn, compared to micronodules that have a diagenetic source.The Sigma REY content of North Atlantic deep-sea sediments is 4 times lower than in Pacific deep-sea sediments. We calculate that the area of seafloor required to extract similar to 10% of the global annual REY demand is similar to 100 km(2) , assuming removal of the upper 1 m of sediment. (C) 2016 Elsevier B.V. All rights reserved.