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How did the Rocky Mountain Trench form?
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Rocky Mountains
Physical features of western North America.
The Rocky Mountain Trench is a geological feature classified as a graben, which is a downfaulted, straight, and flat-bottomed valley.1
Its formation is characterized by the following processes:
- Tectonic Activity: The trench serves as the western margin of the Canadian and Northern Rockies, created as a structural depression through faulting.1
- Glacial Modification: Following its initial formation, the valley was significantly shaped by glaciation.1
- Sedimentation: The floor of the trench has been partially filled with deposits left behind by glacial meltwaters.1
Today, this rugged depression extends approximately 900 miles (1,400 km) and acts as a natural travel route, occupied by the headwaters of several major rivers.2