摘要
大冰期的形成不仅需要气温低,而且需要大量海水转移到大陆上形成冰川。元古代晚期全球规模白云岩建造形成之后,火山作用在洋壳和陆壳上的表现大不相同:洋壳型火山作用是岩浆静静涌出,大量蒸发海水;陆壳型火山作用是猛烈爆发,烘烤碳酸盐岩层产生二氧化碳喷发形成“干冰制冷机制”,使大气降温。洋壳型火山与陆壳型火山共同作用形成大冰期。震旦纪大冰期后开始了显生宙。大冰期与生物的演化发展密切相关的原因是二氧化碳的大量介入。
Not only low temperature is needed for forming the Great Ice Age,but a large mount of seawater transformed to continents is necessary to form glacier. Volcano acted differently on oceanic crust and continental crust after the global-scale dolomitite formation in Late Proterozoic:oceanic crust type volcanic action is characterized by magma gushing out quietly and evaping seawater;continental crust type volcanic action proformed violent eruption,dry ice refrigeration from baked carbonate layer leading to air cooling. Both oceanic crust and continental crust type volcanic actions influenced the forming of the Great Ice Age. After the Sinian Great Ice Age,the Phanerozoic started. A large number of carbon dioxide is the reason why there is close relationship between the Great Ice Age and organic evolution.
出处
《世界地质》
CAS
CSCD
2004年第3期252-254,294,共4页
World Geology
关键词
大冰期
成因
洋壳型与陆壳型
火山作用
干冰制冷
二氧化碳
Great Ice Age
genesis
oceanic crust and continental crust types
volcanic action
dry ice refrigeration
carbon dioxide