POTD March 14, 2017: Big Cottonwood Canyon, Wasatch Range

Big Cottonwood Canyon, Wasatch Range
Photographer: Mike Hylland © 2017

The waters of Lake Blanche reflect Sundial Peak, composed of quartzite of the Big Cottonwood Formation. Rocks in this basin, which formed from sediment that accumulated along a continental margin 900 million years ago, preserve striations (parallel scratches and grooves) that record the down-valley flow of Ice Age glaciers.