Naturita Formation

The Naturita Formation is a Cretaceous Period sedimentary geologic formation, found in western Colorado and eastern Utah. The Naturita Formation is a Cretaceous Period sedimentary geologic formation, found in western Colorado and eastern Utah. It was named for a rock outcrop of the formation located near Naturita, Colorado. The formation overlies the Cedar Mountain Formation, and underlies the Mancos Shale formation, thus occupying the position of sedimentary strata that have historically been called the Dakota Formation. That term is no longer used for Cretaceous strata that were deposited on the western side of the Cretaceous Seaway. In most areas, the Naturita Formation is composed of a lower unit of conglomeratic sandstone, a middle part of lignitic mudstones and coal, and fine- to medium-grained sandstones in the upper part. The Naturita is not uniform in thickness and in many places is very thin or missing so that the Mancos Formation is in direct contact with the Cedar Mountain Formation.