Climatic change recorded in the sediments of the Chew Bahir basin, southern Ethiopia, during the last 45,000 years
Climatic change recorded in the sediments of the Chew Bahir basin, southern Ethiopia, during the last 45,000 years
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DOI：
10.1016/j.quaint.2012.06.028
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发表时间：
2012-10-01
影响因子：
2.2
通讯作者：
Schaebitz, Frank
中科院分区：
文献类型：
--
作者：
Foerster, Verena;Junginger, Annett;Schaebitz, Frank
东非的古环境变化很大，其特点是水分供应的极端波动，这对该地区内外的智人的起源、进化和扩散具有深远的影响。本文介绍了埃塞俄比亚南部Chew Bahir盆地的一个试验性岩心的结果，该岩心记录了过去45 ka的气候历史，重点是非洲湿润期（AHP，类似于15-5 ka calBP）。地球化学、物理和生物学指标表明，Chew Bahir对千年至百年时间尺度的气候波动以及自末次冰盛期以来的岁差周期作出了反应。钾含量的沉积物似乎是一个可靠的代理干旱，表明Chew Bahir的反应，以显着的突然开始和逐步终止的AHP的日照控制湿度增加，框定义明确的干旱阶段（类似于12.8-11.6 ka calBP）对应的新仙女木年代。Chew Bahir的记录与低纬度和高纬度的古气候记录有很好的相关性，表明该遗址对区域和全球气候变化做出了反应。(C)2012 Elsevier Ltd和INQUA。All rights reserved.
East African paleoenvironments are highly variable, marked by extreme fluctuations in moisture availability, which has far-reaching implications for the origin, evolution and dispersal of Homo sapiens in and beyond the region. This paper presents results from a pilot core from the Chew Bahir basin in southern Ethiopia that records the climatic history of the past 45 ka, with emphasis on the African Humid Period (AHP, similar to 15-5 ka calBP). Geochemical, physical and biological indicators show that Chew Bahir responded to climatic fluctuations on millennial to centennial timescales, and to the precessional cycle, since the Last Glacial Maximum. Potassium content of the sediment appears to be a reliable proxy for aridity, showing that Chew Bahir reacted to the insolation-controlled humidity increase of the AHP with a remarkably abrupt onset and a gradual termination, framing a sharply defined arid phase (similar to 12.8-11.6 ka calBP) corresponding to the Younger Dryas chronozone. The Chew Bahir record correlates well with low- and high-latitude paleoclimate records, demonstrating that the site responded to regional and global climate changes. (C) 2012 Elsevier Ltd and INQUA. All rights reserved.