A virtual field trip to see how the geology of the northern Great Plains and the course of the Missouri River have been altered by the great Ice Ages of the past.  The field trip is in several segments, ordered by the stopovers at the ends of each segment.
Along the way we cross the path of the epic journey of Lewis and
Clark.  At some of those points our observations illuminate their
This web site has been created and maintained by Gerald Davidson, PHD
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