【摘 要】
：
地球從诞生之初共经历了5次大型冰期。 1. 休伦冰期 Huronian 24亿年前至21亿年前成铁纪和层侵纪元古宙。 2. 瓦兰吉尔冰期 Cryogenian 8亿年前至6亿3千5百万年前成冰纪元古宙。 3. 安第——撒哈拉冰期 Andean-Saharan 4亿5千万年前至4亿2千万年前奥陶纪和志留纪古生代。 4. 卡鲁冰期 Karoo 3亿6千万年前至2亿6千万年前石炭纪和二叠
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地球從诞生之初共经历了5次大型冰期。
1. 休伦冰期 Huronian
24亿年前至21亿年前成铁纪和层侵纪元古宙。
2. 瓦兰吉尔冰期 Cryogenian
8亿年前至6亿3千5百万年前成冰纪元古宙。
3. 安第——撒哈拉冰期 Andean-Saharan
4亿5千万年前至4亿2千万年前奥陶纪和志留纪古生代。
4. 卡鲁冰期 Karoo
3亿6千万年前至2亿6千万年前石炭纪和二叠纪古生代。
5. 第四纪大冰期Quaternary
200到300万年前至1万年以前。
大型的冰期从地址历史出现的次数及情况来看，总体呈现持续时间越来越短，影响越来越小的现象。
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