Robbie McKay, age 9 of Ric

How  were the ancient Laurentians?

The Laurentian mountains of Canada were in their heyday soave 500 million years ago. They formed the firm backbone of North America before the Rockies and the great Appalacians were born, But the earth is forever changing slowly but surely. Wind and weather wore away their tall tops. The mighty glaciers came and scraped them still lower. Today, this whole region of ancient uplift is but a plateau of rocky hills.

This Laurentian Plateau, or Canadian Shield, covers almost two million square miles. It spreads over almost half of Canada like a giant horseshoe with its tips reaching down into the United States. Most of it is about 1,500 feet above sea level though same of its hills are 6,000 feet high. We cannot tell for sure how high the ancient peaks were, for those old mountains have long since been worn down to the roots. Some experts think they may have been as high as the Sierra Nevada though they were far wider.