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Archive for May 28th, 2015

28 May
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传阅:这么多年,你还叫它“沙尘暴”?

张宏仁(国际地质科学联合会前主席)

细分岩石颗粒

在我国的传统历史文化中,“沙”这个词深入人心。“飞沙走石”“疾风冲寨起,沙砾自飘扬”等等不一而足。而“尘”这个词主要用于家居,极少用于野外的自然现象。很可能在古人的概念中,“沙”这个词既包括“沙”也包括“尘”。

直到现代地质学传到我国,人们才对不同大小的岩石颗粒进行细分为砾、沙、尘、黏土。然而对“尘”这个粒级常常用“粉沙”一词代替,还是没有甩掉“沙”字,“沙”与“尘”仍然没有截然分开。 Read more…