Late Holocene dust provenance at Siple Dome, Antarctica
Late Holocene dust provenance at Siple Dome, Antarctica
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南极洲 Siple Dome 的全新世晚期尘埃来源
DOI：
10.1016/j.quascirev.2021.107271
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发表时间：
2021
影响因子：
4
通讯作者：
Biscaye, Pierre
中科院分区：
文献类型：
--
作者：
Koffman, Bess G.;Goldstein, Steven L.;Winckler, Gisela;Kaplan, Michael R.;Kreutz, Karl J.;Bolge, Louise;Bory, Aloys;Biscaye, Pierre
冰芯中矿物尘埃的成分可以作为古大气环流模式的示踪物，提供源和汇之间的联系。在这里，我们记录了到达大陆西南极洲的灰尘的地球化学组成，晚全新世样品从Siple Dome A冰芯（跨越1030-1800 C.E）。Nd-Sr同位素特征在南极冰芯尘埃样本中是不寻常的。与其他南极尘埃特征相比，Siple Dome数据的特点是低Nd同位素比（低至εNd =-16.3）沿着低Sr同位素比（最高87 Sr/86 Sr = 0.7102）。Sr-Nd同位素比值之间的一个明确的负相关表明两个主要的混合源。低ε Nd值表明古陆壳（太古代-早元古代）的参与，既可能是直接源区，也可能是源区的前体，而低Sr值要求低Rb/Sr比值，这往往反映了高级变质作用。已知的具有这些特征的南极冰是恩德比地的一部分，几乎在南极洲的另一端。第二个端元的同位素特征与南极西部的火山或南美洲的巴塔哥尼亚相一致。Sr-Nd同位素和微量元素丰度也与Gaussberg火山物质之间的混合化学相容，Gaussberg是东南极洲沿海Kaiser Wilhelm II Land的一座小型钾镁煌斑岩火山，其来源是古老的岩石圈地幔，来自巴塔哥尼亚的尘埃或来自西南极火山的物质。我们评估这些潜在的混合方案，并得出结论，Siple Dome的不寻常的地球化学特征可以最好地解释由巴塔哥尼亚灰尘和高斯堡样源的混合物，与旧的侵蚀太古代至早元古代基岩源，如恩德比土地的额外的微小贡献。此外，Siple圆顶灰尘成分是不同的泰勒和克拉克冰川沉积在麦克默多干河谷西部罗斯海的灰尘，排除了干河谷作为晚全新世灰尘源，这一地区的东部罗斯海。
Compositions of mineral dust in ice cores serve as tracers of paleo-atmospheric circulation patterns, providing linkages between sources and sinks. Here we document the geochemical makeup of dust reaching continental West Antarctica, on late Holocene samples from the Siple Dome A ice core (spanning ∼1030–1800 C.E). The Nd–Sr isotope signature is unusual for Antarctic ice core dust samples. Siple Dome data are characterized by low Nd isotope ratios (as low as εNd = −16.3) along with low Sr isotope ratios (highest87Sr/86Sr = 0.7102) compared with other Antarctic dust signatures. A well-defined inverse correlation between Sr–Nd isotope ratios indicates two primary mixing sources. The low εNd-values indicate involvement of ancient (Archean-to-early Proterozoic) continental crust, as either the direct source or as a precursor of the source, and the low Sr-values require low Rb/Sr ratios that often reflect high-grade metamorphism. The known Antarctic terrane with these characteristics is parts of Enderby Land, nearly at the opposite end of Antarctica. The isotopic signature of the second end-member is compatible with West Antarctic volcanoes or Patagonia in South America. The Sr–Nd isotopes and trace element abundances are also chemically compatible with mixing between volcanic material from Gaussberg, a small lamproite volcano in Kaiser Wilhelm II Land in coastal East Antarctica whose source is ancient lithospheric mantle, with dust from Patagonia or material from West Antarctic volcanoes. We assess these potential mixing scenarios and conclude that Siple Dome's unusual geochemical signature can best be explained by a mixture of Patagonian dust and a Gaussberg-like source, with additional minor contributions from old eroded Archean-to-early Proterozoic bedrock sources such as those in Enderby Land. Moreover, Siple Dome dust compositions are distinct from dust deposited on Taylor and Clark Glaciers in the McMurdo Dry Valleys of the western Ross Sea, precluding the Dry Valleys as a late Holocene dust source to this region of the eastern Ross Sea.
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全新世南极洲中部的风尘来源：单晶拉曼光谱的环境限制
影响因子：
5.2
作者：
Chiara I. Paleari;B. Delmonte;S. Andó;E. Garzanti;J. Petit;V. Maggi
通讯作者：
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DOI：
--
发表时间：
1986
期刊：
影响因子：
--
作者：
L. P. Black;J. W. Sheraton;P. James
通讯作者：
P. James
影响因子：
3.9
作者：
K. Panter;P. Kyle;J. Smellie
通讯作者：
K. Panter;P. Kyle;J. Smellie
影响因子：
4.4
作者：
Neff, Peter D.;Bertler, Nancy A. N.
通讯作者：
Bertler, Nancy A. N.
南极洲东部地盾的阿德利地基：与南澳大利亚高勒克拉通进行比较的重大 1.7Ga 热事件的地质和同位素证据；
DOI：
--
发表时间：
1999
期刊：
影响因子：
--
作者：
J. Peucat;R. Ménot;O. Monnier;C. Fanning
通讯作者：
C. Fanning