Roaring River and Alluvial Fan, Rocky Mountain National Park, Colorado. 5-6-2017, 20:03.

The 79-year old Lawn Lake Dam was ruptured and burst in 1982 to send 110 metric kilotons of water down the Roaring River, through Horseshoe Park, and into Estes Park. Many tons of boulders, trees, gravel and sand were swept downhill by the flood before settling in this spot in a fan-shape. This section of the park was pummeled by another wave of similar debris and sediment during the Colorado Flood of 2013.

Source:
Rocky Mountain National Park, Moon (2017).

Nikon D810, AF-S Nikkor 16-35/4G ED VR, 3/5 sec @ f/11, ISO 64, FL=26 mm, WB: 5800K, Kaesemann Polarizer