奥托利特三角洲18O记录了秘鲁的Holocene中期海面温度
C Fred T Andrus1, Douglas E Crowe, Daniel H Sandweiss
1Department of Geology, University of Georgia, Athens, GA 30602-2501, USA. andrus@gly.uga.edu
概括
在全新世纪中期,秘鲁的海面温度更温暖,鱼的耳石证实了这一点. 这种变暖趋势,以及加剧的上升,为过去的气候变化提供了洞察力.
科学领域:
- 古气候学 古气候学
- 海洋生物学 海洋生物学
- 鱼类学 鱼类学 鱼类学
背景情况:
- 鱼耳石,特别是来自秘鲁海鱼 (Galeichthys peruvianus) 的角耳石,可以作为重建过去环境条件的宝贵档案.
- 对石的氧同位素分析为确定过去的海面温度 (SST) 提供了一个代理.
研究的目的:
- 为了重建秘鲁海岸附近的Holocene中期海面温度 (SSTs),使用鱼类耳石的氧同位素分析.
- 调查过去的SSTs,热量级和海洋学现象 (如上游) 之间的潜在相关性.
主要方法:
- 从考古遗址 (奥斯特拉和西切斯) 挖掘和分析秘鲁海 (Galeichthys peruvianus) 的斜耳石.
- 氧同位素对耳石的分析,以确定过去的SSTs.
- 从相关的动物群组中分析了食物营养水平,种群多样性和公平性.
主要成果:
- 来自奥斯特拉的耳岩 (6010年+/- 90年BP) 表示夏季SST大约比现在高3°C.
- 来自西切斯的耳岩 (6450年+/- 110年BP) 记录的平均年温度比现代条件高3°C至4°C.
- 动物数据支持同位素解释,并建议大约5000年B.P.后,秘鲁-智利电流上升加剧.
结论:
- 在全新世纪中期的秘鲁沿海水域,海面温度相比现在要高得多.
- 在5000年B.P.之后,秘鲁-智利电流上升的加剧. 可能影响了这些温度变化.
- 鱼耳石是该地区过去海洋和气候条件的可靠记录器.
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