Cutler Formation

The Cutler is a rock unit that is spread across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian stage. In Arizona and Utah it is often called the Cutler Group but the preferred USGS name is Cutler Formation'. Its subunits, therefore, are variously called formations or members depending on the publication. This article will use the national standard set by the USGS. Members (youngest to oldest ):

• Elephant Canyon (Utah)
• Halgaito (Arizona, Colorado, New Mexico, Utah)
• Cedar Mesa Sandstone (Arizona, Utah)
• Organ Rock Shale (Arizona, Colorado, New Mexico, Utah)
• White Rim Sandstone (Utah)
• De Chelly Sandstone (Arizona, Colorado, New Mexico, Utah)

There is no designated type locality for the Cutler. It was named by Cross and Howe in 1905 after Cutler Creek, which enters Uncompahgre River about 4 miles north of Ouray, Colorado. Baker and Reeside revised Cross and Howe's work in 1929 by dividing the formation into the Halgaito Tongue (base), Cedar Mesa Sandstone Member, Organ Rock Tongue, and White Rim Sandstone Member. Cutler's geographic extent was established by Wood and Northrop in 1946. In 1958 Wengerd and Matheny raised the formation to group rank, but as of 2005 the USGS does not recognize the suggested change.

Cutler outcrops are found in these geologic locations:

• Black Mesa Basin
• Paradox Basin
• Piceance Basin
• San Juan Mountains province
• San Juan Basin
• Uinta Basin