Question

Which parts of north america have not been added to the continent since the precambrian?

Answer 1

Stable regions of the craton where shields are covered by sedimentary rocks are called platforms.

Precambrian rocks are often called basement rocks because they lie beneath a covering of fossil-bearing sedimentary strata.

Various Precambrian provinces can be delineated within the North American continent, based on radiometric ages of rocks, style of folding, and differences in trends of faults and folds.

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