Mountains in Motion
Though the visible glaciers appear remote - gleaming between distant peaks - the valley below is strewn with signs of masses glaciation: stranded boulders, gouged-out ponds, and gravel outwash plains. The last big glacial advance plowed through this valley about 10,000 years ago. To a geologist's eye, the landscape is still active with glaciers. Denali's wandering meltwater rivers, cloudy with glacial silt and rock fragments, are evidence of ongoing glaciation and mountain carving.
Hot Rocks
The many-colored (polychrome) rocks are hardened lava, from a period of mountain building 100 million years ago. That timeframe seems unimaginably distant - yet this area is experiencing continued seismic activity. Earthquake tremors are frequent. As the crustal plates along the Denali fault keep grinding together, mountains of the Alaskan range may still be rising.
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