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太白山(3767 m)是我国东部公认发育过第四纪冰川的山地,研究该区的第四纪冰川发育历史以及规模对第四纪环境演变具有重要的科学意义.然而,本区的第四纪冰川发生时代长期以来没有得到很好的解决,只有外国学者Rost在黑河谷地上游的内侧碛垄进行热释光(TL)断代,认为冰川发生的时限距今大约19 ka,对应末次冰盛期.本文运用陆生宇宙成因核素法(TCN)对三爷海、二爷海冰坎基岩暴露面进行了10Be定年,时代距今为18.62±1.08~16.87±0.95,16.88±1.08~15.07±0.92 ka,表明该区在末次冰期晚期经历了显著的冰川作用.根据三爷海到二爷海的直线距离和高差以及两级冰坎的平均暴露年代,在不考虑晚冰期和冰后期气候差异的情况下,推断冰川在水平和垂向上的退缩速度分别为0.396和0.09 m a?1,冰川在0.73~1.3 ka之间脱离山顶,永久积雪从此消失不见.
The Taibai Mountain (3767 m) is a mountain recognized as a member of the Quaternary glacier in the eastern part of China, and it is of great scientific significance to study the history and scale of the Quaternary glaciations in this area for the evolution of the Quaternary Environment. However, The era of glacier has not been solved well for a long time. Only the scholar Rost of the United States carried out the TL TL dating on the inner moraine ridge of the upper reaches of the Heihe Valley. The time limit of glacier occurrence is about 19 ka, corresponding to the last ice age In this paper, the Terrestrial Cosmogenic Nuclide Method (TCN) was used to determine the exposed surface of the Sanyehai and Eryan sea ice cancun rocks for 10Be dating from 18.62 ± 1.08 ~ 16.87 ± 0.95 and 16.88 ± 1.08 ~ 15.07 ± 0.92 ka, indicating that the area experienced significant glacial glaciation in the late Last Ice Age.According to the straight line distance and elevation difference from Sanye Sea to Erye Sea and the mean exposure time of two glaciers, In the case of difference, it is inferred that the horizontal and vertical retreat rates of the glaciers are 0.396 and 0.09 ma -1, respectively. The glaciers are separated from the top between 0.73 and 1.3 ka, and the permanent snow disappears.