This is the Aqua Zarca Member of the Chinle Formation, which is the basalmost unit of the Chinle in the Chama Basin. This is a very colorful unit of interbedded sandstone and mudstone intervals, the base of which is highly mottled as is common in the lower units. Jeff Martz for scale. Photo taken by Randall Irmis.
Kurt Gödel's Open World
2 hours ago in The Curious Wavefunction