The areas covered by this material were so vast that the ice that deposited it must have been a continentalglacier larger than Greenland or Antarctica.
这种物质覆盖的区域十分巨大，因此使其沉积下来的冰一定是比格陵兰岛或南极洲更大的大陆冰川。
2
Beginning 25,000 years ago, the Bow Valley glacier ground through the region before being overtaken by a continentalglacier.
从2万5千年前开始，弓河谷冰川穿过了整个峡谷，之后被大陆冰川所取代。
3
Greenland and Antarctica are covered by continental glaciers. Pieces at the ocean edge of a continentalglacier break off and become icebergs floating on the ocean.