POTD August 5, 2013: Island in the Sky District, Canyonlands National Park, San Juan County, Utah

Island in the Sky District, Canyonlands National Park, San Juan County, Utah
Photographer: Taylor Boden

The La Sal Mountains laccolith (a shallow, mushroom-shaped igneous intrusion) of Oligocene age rises above the red Mesozoic and Paleozoic sedimentary rocks exposed in the Colorado River drainage. Washer Woman Arch, visible in the upper part of the small butte in the middle foreground, is eroded out of the Triassic-Jurassic-aged Wingate Sandstone.