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半个世纪以来,关于长江中下游一些山地在第四纪时是否发生过冰川活动的问题,一直存在着不同的看法,争论的关键之一是对一些“泥砾”的成因的认识:有人认为是冰川作用的产物;有人认为是泥石流堆积。为什么会有如此大的分歧呢?究其原因,盖出于对泥砾成因属性的鉴别方法不同而得出了不同的结论。泥砾按成因可分为三种类型:(1)气—地,如坡积泥砾;(2)水—地,如泥石流堆积或洪积泥砾;(3)冰—地,如冰碛泥砾。但如何鉴别泥砾的成因却至今仍有不同的认识。不久前,有的地学工作者曾根据泥砾中细颗粒组分的粒度结构特征,来区别冰碛泥砾与(洪积)
For half a century, there have been different opinions on whether or not glacier activities took place in some mountains in the middle and lower reaches of the Yangtze River during the Quaternary. One of the keys to the debate is the understanding of some of the causes of “mud” Some people think that the product of the role of glaciers; some people think that debris flow accumulation. Why is there such a big difference? The reason for this is that different conclusions can be drawn from the different methods of identifying the genetic causes of mud gravel. Boulders can be divided into three types according to their causes: (1) gas-land, such as slope mud; (2) water-land, such as mud-rock accumulation or alluvial mud gravel; (3) ice- Boulders. However, there are still different understandings on how to identify the causes of mud and gravel. Not long ago, some geoscientists have distinguished the morass of muddy gravel from the (alluvial)