Precambrian Shield

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Ancient bedrock emerges from the ground across a large expanse of Canada known as the Precambrian Shield, or sometimes the Canadian Shield.

As geology became a science early geologist assigned names to different layers of rock, based on the kinds of fossils they found in those rocks. As outcroppings from these different layers were found all around Planet Earth, they determined that the layer known as Cambrian was the oldest fossil-bearing layer.

Determining the age of rocks too old to have fossils was much more difficult, and these rocks are known as Precambrian.

Recent glaciations scraped the earth and upper layers of rock off of the Shield.