Here at the lower portion of Bells Canyon, the reds of maples and scrub oak and the yellows of aspen and cottonwood trees cover a varied geology. During the Ice Age, glaciers descended the full length of the canyon to touch the shores of ancient Lake Bonneville making it only one of two places in the Western US (the other is in California) where ice descended to water. The residual deposits sloughed off the sides of the glacier are still visible to the north of the reservoir, with a notch cut by the Wasatch Fault.
Further up the canyon, across the lake, the 1.8+ Billion year old Big Cottonwood formation shows a gnarled cliff of metamorphosed sedimentary rock. Even further, spires of granite rise above the canyon, the result of magma intrusions from below during the mountain building of the last 65 million years.