Oxbow Overlook at Theodor Roosevelt NP, North Unit, ND Filename: CEM009448-TRNP-ND-USA.jpg
Grassland in Theodor Roosevelt NP, North Unit, ND Filename: CEM009450-TRNP-ND-USA.jpg
Grassland in Theodor Roosevelt NP, North Unit, ND, EDGE OF A GLACIER These small boulders are clues to a fascinating story. Geologists believe they were ripped from bedrock 400 miles north in Canada and carried to this point by a great glacier which covered nearly all North America north and east of here. The ice melted thousands of years ago, but these rocks, called "erratics" because they are 'out of place'. are clear evidence the glacier once covered this area. Filename: CEM009451-TRNP-ND-USA.jpg