At the geologic time,the earth had undergone the glacial stages:Sinian ice age,Carboniferous~Permian ice age and Quaternary ice age.According to the theory of petrology and three standards of professor Li Siguang to determine fossil glacier,the result of
王长生.渝鄂湘黔毗邻地区古冰川研究[J].重庆工商大学学报(自然科学版),2006,(2): WANG Chang-sheng. A study of Paleoglacial at boundary of Chongqing, Hubei, Hunan and Guizhou provinces[J]. Journal of Chongqing Technology and Business University(Natural Science Edition),2006,(2):