他的理论是，随着船只的使用，人们沿着因海平面下降而暴露的大陆架逐渐移居到未冻结成冰的区域。

He theorized that with the use of watercraft, people gradually colonized unglaciated refuges and areas along the continental shelf exposed by the lower sea level.

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大约10%的岛已冻结成冰。

Approximately 10% of the island is glaciated.

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已冻结成冰的火山爆发会毁掉冰田，就想1980年当70%圣海伦山的冰盖就是这样被摧毁的。

Eruptions at glaciated volcanoes typically destroy ice fields, as they did in 1980 when 70 of Mount Saint Helens ice cover was demolished.

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