glaciation

noun [抽象名词][地质] 冰川作用；冻结成冰

The problem with ascribing all tillites to glaciation, however, is that tillite deposits are widespread in Precambrian sediments.
然而，使所有的黑土形成冰川作用的问题是，在前寒武纪沉积物中广泛分布有黑土。