Geochemical provenance analysis of fine-grained sediment revealing Late Miocene to recent Paleo-Environmental changes in the Western Ross Sea, Antarctica
Geochemical provenance analysis of fine-grained sediment revealing Late Miocene to recent Paleo-Environmental changes in the Western Ross Sea, Antarctica
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DOI：
10.1016/j.gloplacha.2010.05.001
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发表时间：
2012-10
影响因子：
3.9
通讯作者：
Donata Monien;G. Kuhn;H. Eynatten;F. Talarico
中科院分区：
文献类型：
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作者：
Donata Monien;G. Kuhn;H. Eynatten;F. Talarico
散装化学细粒沉积物成分从南部维多利亚土地冰川沉积物提供了显着的制约重建沉积物源模型在麦克默多声音在晚新生代。使用非破坏性AVAATECH XRF岩心扫描仪（XRF-CS）对1285米长的安德里尔麦克默多冰架项目（MIS）沉积物岩心AND-1B获得了高分辨率（100万）地球化学数据。该数据集由离散样品的高精度化学分析（XRF和ICP-OES）补充。统计分析揭示了三种地球化学相，它们被解释为代表AND-1B岩心中回收的沉积物的以下来源：1）当地麦克默多火山群（MVG）岩石，2）罗斯岛西部的横贯南极山脉岩石（W TAM），以及3）更南部地区的横贯南极山脉岩石（S TAM）。数据表明，结合其他沉积物相分析（McKay等人，2009年）和物源情景（Talarico和Sandroni，2009年）表明，钻探现场的杂岩主要由当地来源（MVG）控制，并被解释为指示寒冷的极地条件下的干基冰。MVG被解释为指示寒冷的极地条件与干基冰。MVG和W TAM的混合物被解释为代表极地条件，S TAM相被解释为代表开阔海洋条件。在AND-1B岩心的地球化学相的向下核心的变化被解释为代表五个主要的古气候阶段在过去的14 Ma。具有主要MVG影响的寒冷极地条件发生在1045 mbsf以下和120 mbsf以上。一段温暖的气候条件下，广泛的峰值的S TAM的影响的特点，其余的核心，这是中断的一段从525至855 mbsf的交替影响的MVG和W TAM。
Bulk chemical fine-grained sediment compositions from southern Victoria Land glacimarine sediments provide significant constraints on the reconstruction of sediment provenance models in the McMurdo Sound during Late Cenozoic time. High-resolution (∼1ka) geochemical data were obtained with a non-destructive AVAATECH XRF Core Scanner (XRF-CS) on the 1285m long ANDRILL McMurdo Ice Shelf Project (MIS) sediment core AND-1B. This data set is complemented by high-precision chemical analyses (XRF and ICP-OES) on discrete samples. Statistical analyses reveal three geochemical facies which are interpreted to represent the following sources for the sediments recovered in the AND-1B core: 1) local McMurdo Volcanic Group (MVG) rocks, 2) Transantarctic Mountain rocks west of Ross Island (W TAM), and 3) Transantarctic Mountain rocks from more southerly areas (S TAM). Data indicate in combination with other sediment facies analyses (McKay et al., 2009) and provenance scenarios (Talarico and Sandroni, 2009) that diamictites at the drill site are largely dominated by local sources (MVG) and are interpreted to indicate cold polar conditions with dry-based ice. MVG is interpreted to indicate cold polar condition with dry-based ice. A mixture of MVG and W TAM is interpreted to represent polar conditions and the S TAM facies is interpreted to represent open-marine conditions. Down-core variations in geochemical facies in the AND-1B core are interpreted to represent five major paleoclimate phases over the past 14Ma. Cold polar conditions with major MVG influence occur below 1045mbsf and above 120mbsf. A section of warmer climate conditions with extensive peaks of S TAM influence characterizes the rest of the core, which is interrupted by a section from 525 to 855mbsf of alternating influences of MVG and W TAM.