南极冰盖象一个浅的大圆屋顶,罩在南极大陆表面上。几亿年来,此大陆内部积累的冰的重量把边远的冰从冰盖的斜坡上推下来到海中。没有人真正知道冰已覆盖了南极大陆多长时间。有些地质学家认为,距今3百万年前,南极的气候相当温和,甚至森林密布。但是,爱丁堡大学的地质学家D·苏格登 The Antarctic ice sheet resembles a shallow dome, covered on the Antarctic continent. For hundreds of millions of years, the weight of ice accumulated in this continent pushed the remote ice from the ice-covered slope into the sea. No one really knows how long ice has covered the Antarctic continent. Some geologists believe that the Antarctic climate is mild and even densely populated 3 million years ago. However, D. Gedeng, a geologist at the University of Edinburgh,