Seawater 87Sr/86Sr ratios along continental margins: Patterns and processes in open and restricted shelf domains
Seawater 87Sr/86Sr ratios along continental margins: Patterns and processes in open and restricted shelf domains
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大陆边缘海水 87Sr/86Sr 比率：开放和受限陆架区域的模式和过程
DOI：
10.1016/j.chemgeo.2020.119874
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发表时间：
2020
期刊：
影响因子：
3.9
通讯作者：
V. Chavagnac
中科院分区：
文献类型：
--
作者：
S. El Meknassi;G. Dera;M. de Rafélis;C. Brahmi;F. Lartaud;F. Hodel;C. Jeandel;L. Menjot;S. Mounic;Manuel Henry;Philippe Besson;V. Chavagnac
为了更好地限制在边缘域没有任何河流输入的Sr同位素收支，我们分析了化学成分和87 Sr/86 Sr比值的沃茨和贝壳从四个位置：两个沿海泻湖，一个半远洋平台和一个开放的海洋货架。我们的研究结果突出了贫营养海洋沃茨（OOW）典型的87 Sr/86 Sr比值（即，0.709172 ± 0.000023）在太平洋Tatakoto环礁和沿着地中海海岸到近海样带（Banyuls-sur-Mer，BSM约25 km）。这证明，海洋输入贫营养区仍然是主要的锶源在开阔的大陆架地区相比，海底地下水排放（SGD）或颗粒溶解的影响。在BSM中，只有前滨数据更具放射性，可能是由于雨水混合，当地地下水泉或更有效的粒子溶解在潮间带。在限制区域，我们报告可变的87 Sr/86 Sr之间的Salses-Leucate（法国）和Oualidia（摩洛哥）泻湖的比例。第一个具有OOW的典型的不稳定的87 Sr/86 Sr比，除了接近SGD。在Oualidia，87 Sr/86 Sr比值从大西洋入口附近的OOW值到泻湖内部上游的放射成因值逐渐减少，减少了1.2 × 10− 3。这些差异取决于几个因素，包括泻湖的渗漏，限制或堵塞的形态调制海洋Sr输入，但也SGD通量whose 87 Sr/86 Sr的比率和Sr浓度是高度可变的，根据岩溶含水层中的岩石浸出的性质。在Oualidia，低的87 Sr/86 Sr比值对应于中生代碳酸盐岩溶解产生的高Sr浓度（高达150 μmol·l−1），导致SGD通量占当地Sr收支的60%。通过数据汇编，我们表明，相似的87 Sr/86 Sr梯度和过程中占主导地位，在整个地中海尺度。最后，我们假设，高海岸水滞留时间也可以解释异常coastal 87 Sr/86 Sr比值和水的质量限制，SGD，生物吸附和早期成岩过程的组合，可以降低海水锶浓度在一些边缘地区。
To better constrain the Sr isotope budget in marginal domains without any fluvial inputs, we analyzed the chemical composition and87Sr/86Sr ratio of waters and shells from four locations: two coastal lagoons, one hemipelagic platform and one open marine shelf. Our results highlight homogeneous87Sr/86Sr ratios typical of oligotrophic oceanic waters (OOW) (i.e., 0.709172 ± 0.000023) in the Pacific Tatakoto atoll and along a Mediterranean shore to offshore transect (~25 km off Banyuls-sur-Mer, BSM). This attests that oceanic inputs from oligotrophic areas remain the main Sr source in open shelf areas compared with submarine groundwater discharges (SGD) or particulate dissolution influences. In BSM, only foreshore data are more radiogenic, possibly due to rainwater mixing, local groundwater springs or more efficient particle dissolution in the intertidal zone. In restricted areas, we report variable87Sr/86Sr ratios between the Salses-Leucate (France) and Oualidia (Morocco) lagoons. The first one has homogeneous87Sr/86Sr ratio typical of OOW except close to SGD. In Oualidia,87Sr/86Sr ratios decrease by 1.2 × 10−3from OOW values close to the Atlantic inlet to progressively less radiogenic ones upstream within the interior of the lagoon. These differences depend on several factors including the leaky, restricted or choked morphology of lagoons modulating the oceanic Sr inputs, but also SGD fluxes whose87Sr/86Sr ratios and Sr concentrations are highly variable according to the nature of rocks leached in karstic aquifer. In Oualidia, the low87Sr/86Sr ratios correspond to high Sr concentrations (up to 150 μmol·l−1) issued from the dissolution of Mesozoic evaporites, leading to SGD fluxes accounting for 60% of the local Sr budget. Through data compilation, we show that similar87Sr/86Sr gradients and processes prevail at the whole Mediterranean scale. Finally, we postulate that high coastal water retention times can also account for anomalous coastal87Sr/86Sr ratios and that the combination of water mass restriction, SGD, bioadsorption and early diagenetic processes could decrease seawater Sr concentrations in some marginal areas.
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影响因子：
3.2
作者：
Tanhua;Hainbucher;Schroeder;Cardin;Álvarez;Civitarese
通讯作者：
Civitarese
DOI：
10.1016/j.dsr2.2017.11.014
发表时间：
2017-12
期刊：
Deep Sea Research Part II: Topical Studies in Oceanography
影响因子：
--
作者：
B. Teichert;N. Chevalier;N. Gussone;G. Bayon;E. Ponzevera;L. Ruffine;H. Strauss
通讯作者：
B. Teichert;N. Chevalier;N. Gussone;G. Bayon;E. Ponzevera;L. Ruffine;H. Strauss
量化海水中河流颗粒溶解对海洋化学的影响
影响因子：
5.3
作者：
Jones M
通讯作者：
Jones M
影响因子：
5
作者：
Krabbenhoeft, A.;Eisenhauer, A.;Wallmann, K.
通讯作者：
Wallmann, K.