山东蒙山国家地质公园佛塔谷堆积了大量的巨砾,其形成原因存在着很大的争论。探讨蒙山佛塔谷砾石堆积体的形成年代有助于了解蒙山环境演化和气候变化。关于佛塔谷砾石的微地貌已有相关作者探讨,本文在前人研究的基础上从拦马墙砾石堆积体的宇生核素10Be暴露年代以及全新世以来的气候环境和人类文化等方面进行探讨。研究结果表明: ①拦马墙砾石宇生核素10Be暴露年代结果为5.0 ~ 6.0 ka BP左右,不支持先前发表的8.2 ka BP拦马冰期的结论; ②全新世以来山东蒙山区域处于一个暖湿的环境下,尽管有几次降温事件,但是不足以提供形成冰川的条件。
英文摘要:
There are a lot of huge boulders in the Lanmaqiang (means wall for blocking horses),Fota (means Pagoda) Valley in the Mengshan Mountain,Mengshan National Geopark,Shandong Province. There is a big debate about the reasons for its formation. It is helpful to understand the formation of gravel deposits in the Fota Valley,Mengshan Mountain,to understand the environmental evolution and climate change in Mengshan Mountain area. The writers have discussed the micro-geomorphology of gravel in Fota Valley. This article focuses on the in situ terrestrial cosmogenic nuclide (TCN) 10Be exposure dating of Lanmaqiang boulders deposits and the climate environment and human culture of Shandong Province since the Holocene. The results of the study indicate that: ① The 10Be exposure ages of the Lanmaqiang boulders were about 5.0 ~ 6.0 ka BP,which does not support the conclusion of the previously published8.2 ka BP Lanma glacial periods ; ② since Holocene,the Mengshan Mountain area of Shandong Province was in a warm and humid environment. Despite several cooling events,it was not enough to provide the conditions for the formation of glaciers.