Image of the Day — Northern Sandia Mountains

The 1420 million year old Sandia Granite is overlain by Pennsylvanian Sandia Formation (slope) and Madera Group limestone (white cliffs). There are also scattered esposures of Missippian rocks above the Great Unconformity. This is actually more precisely a nonconformity, or unconformity between crystalline rocks and stratified rocks, that represents more than one billion years of missing rock record at this location.

This view was taken from the Knife Edge of the Shield, the largest cliff face in the range.  The shadow shows the profile of the 45 degree Knife Edge.