Such an awesome view of the Rocky Mountain Trench, one of my favorite regions of North America.
From the article:
While geologists still debate the circumstances that created the trench, the section seen here likely formed due to underlying normal faults that emerged in the aftermath of tectonic collisions that pushed up the mountains. Normal faults are ruptures in the rocky outer part of Earth—the lithosphere—that generally emerge when land surfaces get stretched out. In a normal fault, one piece of lithosphere drops down relative to another.
In this case, the normal faults that underlie the southern half of the Rocky Mountain Trench likely formed as the lithosphere stretched after a period of mountain building that occurred between 185 million and 55 million years ago. At least three chains of islands plowed into the western coast of North America, forming mountains by bulldozing rock layers onto North America. In this part of western Canada, mountain building progressed from southwest to northeast, so the Columbia Mountains are older than the Canadian Rockies. With the normal faults in place, rivers and glaciers have since worked to widen and deepen the trench through erosion.
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