Geology
The canyons in this region were carved out by ice age glaciers, which left behind U-shaped valleys, moraines, hanging valleys, and steeply carved granite mountains, cliffs, and cirques, all of which are visible within Blodgett Canyon. The glacial valley is carved into granitic rocks of the Bitterroot Lobe of the Idaho Batholith, a Late Cretaceous to Paleocene intrusive body emplaced by subduction beneath the western margin of North America.
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