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冰川漂砾的形成年代通常难以直接测定,并且漂砾形成以后是否被再次搬运或者移动过,更是无法知道。本文研究发现,通过测试砾石不同部位的宇生同位素,不仅可以测定砾石形成的时代,而且可以确定砾石再次被搬运或者被翻转的年代,从而恢复砾石运动的历史。本文以石英中生成的宇生同位素~(10)Be,对青藏高原东南部海子山的冰川漂砾进行了探讨,结果表明该砾石形成于倒数第二次冰期(186～128 ka BP之间),在末次冰期中再次被冰川搬运,使之反转。该方法不局限于~(10)Be和冰川漂砾,也适用于其他陆面岩石中生成的宇生同位素以及其他成因的石块或者砾石。因此为探讨冰川作用、泥石流活动、重力崩塌等过程提供了一种重要的方法和技术途径。
The formation of glacial boulders is usually difficult to measure directly, and it is impossible to know whether the boulders were transported or moved again after their formation. The study found that by testing the different parts of the gravel Miocene isotopes, not only can measure the age of gravel formation, but also to determine the gravel is again being transported or turned over to restore the history of gravel movement. In this paper, we investigate the glacial boulder of Haizishan, southeastern Qinghai-Tibet Plateau, using the isotope of ~ (10) Be, which was generated in quartz. The results show that the gravel formed in the penultimate glacial period (186 ~ 128 ka BP) , Was again transported by the glacier during the last ice age, reversing it. The method is not limited to ~ (10) Be and glacial boulders, but also to the metasoma and other generous rocks or gravels produced in other land-surface rocks. Therefore, it provides an important method and technical approach to explore the role of glaciers, debris flow activities, gravity collapse and other processes.