Lewis Shale
Lewis Shale
NPS Photo by Phil Varela
NPS Photo by Tom Lyttle Petrified Tree Stump in Lewis Shale The Lewis Shale is an olive-gray marine shale thinly interbedded with claystone, siltstone and sandstone as well as scattered beds of limestone. It overlies the Cliff House Sandstone and is exposed only near the northern boundary of the park. This unit was deposited at water depths greater than the Cliff House Sandstone and represents the last significant transgression of the Western Interior Seaway into northwestern New Mexico. Few fossils have been found in the Lewis Shale unit within the park. |
Did You Know?
Many buildings got the names you see at the park today during an exploration under Lieutenant James Simpson in 1849. Simpson recorded the names given to him by one of his guides, Carravahal. They have linguistic origins in Spanish, Navajo, and Hopi.