Deglacial seasonal and sub‐seasonal diatom record from Palmer Deep, Antarctica
Deglacial seasonal and sub‐seasonal diatom record from Palmer Deep, Antarctica
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南极洲帕尔默深渊的冰消季节和次季节硅藻记录
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
E. Domack
中科院分区：
文献类型：
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作者：
E. Maddison;J. Pike;A. Leventer;E. Domack
南极半岛是南极洲对气候变化最敏感的地区之一。在这里，生态和冰冻圈系统对气候波动作出迅速反应。南极半岛Palmer Deep盆地I的ODP 1098站的海洋沉积物柱样中，发现了末次冰消期沉积的4.4 m厚的硅藻软泥层。这一冰消层积间隔直接沉积在冰海杂岩上，因此是在全球公认的气候快速变化时期。超高分辨率冰消记录使用SEM背散射电子图像和二次电子图像进行分析。层状至薄层橙子棕色硅藻软泥（接近单属透明毛藻角毛藻属）休眠孢子）与蓝灰色陆源沉积物（开放水域硅藻物种）交替。这些离散的纹层被解释为南方春季和夏季的信号，分别与冬季沉积可以忽略不计。在夏季纹层中反复观察到亚季节性的亚纹层，表明整个夏季陆架沃茨的变化。潮汐周期、高风暴强度和/或绕极深水侵入大陆架造成了整个季节提高特定物种生产力的条件。版权所有© 2005年约翰威利父子有限公司。
The Antarctic Peninsula is one of the most sensitive regions of Antarctica to climate change. Here, ecological and cryospheric systems respond rapidly to climate fluctuations. A 4.4 m thick laminated diatom ooze deposited during the last deglaciation is examined from a marine sediment core (ODP Site 1098) recovered from Basin I, Palmer Deep, western Antarctic Peninsula. This deglacial laminated interval was deposited directly over a glaciomarine diamict, hence during a globally recognised period of rapid climate change. The ultra‐high‐resolution deglacial record is analysed using SEM backscattered electron imagery and secondary electron imagery. Laminated to thinly bedded orange‐brown diatom ooze (near monogeneric Hyalochaete Chaetoceros spp. resting spores) alternates with blue‐grey terrigenous sediments (open water diatom species). These discrete laminae are interpreted as austral spring and summer signals respectively, with negligible winter deposition. Sub‐seasonal sub‐laminae are observed repeatedly through the summer laminae, suggesting variations in shelf waters throughout the summer. Tidal cycles, high storm intensities and/or intrusion of Circumpolar Deep Water onto the continental shelf introduced conditions which enhanced specific species productivity through the season. Copyright © 2005 John Wiley & Sons, Ltd.