标题: 问个知识点 [打印本页] 作者: mrj1104 时间: 2011-8-18 22:48 标题: 问个知识点 NEW theories propose that catastrophic impact of asteroids and comets may have caused reversals in the Earth’s magnetic field , the onset of ice ages ,splitting apart continents 80 million years ago ,and great volcanic eruptions A splitting apart continents B the splitting apart of continents C split apart continent D continent split apart E continent that were split apart