231Pa/230-Th: A proxy for upwelling off the coast of West Africa
231Pa/230-Th: A proxy for upwelling off the coast of West Africa
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DOI：
10.1016/j.nimb.2009.10.123
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发表时间：
2010-04-01
影响因子：
1.3
通讯作者：
Synal, Hans-Arno
中科院分区：
文献类型：
--
作者：
Christl, Marcus;Lippold, Joerg;Synal, Hans-Arno
Pa-231在地球科学中有着广泛的应用，包括碳酸盐的铀系不平衡定年和在冰期/间冰期时间尺度上重建海洋环流或生物生产力。在这里，我们提出了第一个Pa-231配置文件，从海洋沉积物芯（GeoB 3722）位于大上升流区关闭西非（北开普省盆地）与加速器质谱（AMS）测量。与Th和U数据（用ICP-MS获得）一起，计算了过去30，000年的Pa-231/Th-230比值。我们的研究结果表明，站点GeoB 3722位于风驱动的上升流区在冰期，而它突然变成一个开放的海洋区域，约14,000年BP。大型风力驱动的上升流区西非的空间转移是一致的想法，大气环流模式以及海洋环流显着改变了末次冰期间冰期过渡。(C)2009爱思唯尔有限公司版权所有。
Pa-231 has widespread applications in the earth sciences including uranium series disequilibrium dating of carbonates and the reconstruction of ocean circulation or bio-productivity on glacial/interglacial time-scales. Here we present the first Pa-231 profile from a marine sediment core (GeoB3722) located in the large upwelling area off West Africa (Northern Cape Basin) measured with Accelerator Mass Spectrometry (AMS). Together with the Th and U-data (obtained with ICP-MS) Pa-231/Th-230 ratios were calculated covering the past 30,000 yr. Our results indicate that site GeoB3722 was located in the wind driven upwelling area during glacial times while it abruptly turned into an open ocean area at about 14,000 yr BP. A spatial shift of the large wind driven upwelling area off West Africa is consistent with the idea that atmospheric circulation patterns as well as ocean circulation dramatically changed at the last glacial interglacial transition. (C) 2009 Elsevier B.V. All rights reserved.