Geology and Features
Mount McKinley is a granitic pluton. It has been uplifted by tectonic pressure while at the same time, erosion has stripped away the (somewhat softer) sedimentary rock above and around the mountain.
The forces that lifted Mount McKinley—the subduction of the Pacific plate beneath the North American plate—also raised great ranges across southern Alaska. As that huge sheet of ocean-floor rock plunges downward into the mantle, it shoves and crumples the continent into soaring mountains which include some of the most active volcanoes on the continent. Mount McKinley in particular is uplifted relative to the rocks around it because it is at the intersection of major active strike-slip faults (faults that move rocks laterally across the Earth's surface) which allow the deep buried rocks to be unroofed more rapidly compared to those around them.
McKinley has a summit elevation of 20,320 feet (6,194 m) above sea level, making it the highest peak in North America. Measured from base to peak, it is also the world's tallest mountain on land. McKinley sits atop a sloping plain with elevations from 300 metres (1,000 ft) to 900 metres (3,000 ft), for a base-to-peak height of 5,300 to 5,900 metres (17,000 to 19,000 ft). (Mount Everest, on the other hand, sits atop the Tibetan Plateau at a much higher base elevation. Base elevations for Everest range from 4,200 m (13,800 ft) on the south side to 5,200 m (17,100 ft) on the Tibetan Plateau, for a base-to-peak height in the range of 3,650 to 4,650 metres (12,000 to 15,300 ft). However, McKinley's base-to-peak height is little more than half that of the 10,200 metres (33,500 ft) of the volcano Mauna Kea, which lies mostly under water.)
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“Each reader discovers for himself that, with respect to the simpler features of nature, succeeding poets have done little else than copy his similes.”
—Henry David Thoreau (1817–1862)