The epic 3 billion-year
story of how our continent came to be. From the palm trees that once
flourished in Alaska to titanic eruptions that nearly tore the Midwest
in two, discover how forces of almost unimaginable power gave birth to
North America.
http://www.pbs.org/wgbh/nova/earth/making-north-america.html#north-america-origins
Note that other related North America episodes are available using this link.