The Entrada Sandstone is a formation in the San Rafael Group found in the U.S. states of Wyoming, Colorado, northwest New Mexico, northeast Arizona, and southeast Utah. Part of the Colorado Plateau, this formation was deposited during the Jurassic Period sometime between 180 and 140 million years ago in various environments, including tidal mudflats, beaches, and sand dunes. The Middle Jurassic San Rafael Group was dominantly deposited as ergs in a desert environment around the shallow Sundance Sea.
The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part of the Colorado Plateau and Basin and Range, this red sandstone was laid down in the Lower Triassic and possibly part of the Middle Triassic, around 240 million years ago.
The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In New Mexico, it is often raised to the status of a geological group, the Chinle Group. Some authors have controversially considered the Chinle to be synonymous to the Dockum Group of eastern Colorado and New Mexico, western Texas, the Oklahoma panhandle, and southwestern Kansas. The Chinle Formation is part of the Colorado Plateau, Basin and Range, and the southern section of the Interior Plains. A probable separate depositional basin within the Chinle is found in northwestern Colorado and northeastern Utah. The southern portion of the Chinle reaches a maximum thickness of a little over 520 meters (1,710 ft). Typically, the Chinle rests unconformably on the Moenkopi Formation.
The Glen Canyon Group is a geologic group of formations that is spread across the U.S. states of Nevada, Utah, northern Arizona, north west New Mexico and western Colorado. It is called the Glen Canyon Sandstone in the Green River Basin of Colorado and Utah.
The San Rafael Group is a geologic group or collection of related rock formations that is spread across the U.S. states of New Mexico, Arizona, Utah and Colorado. As part of the Colorado Plateau, this group of formations was laid down in the Middle Jurassic during the Bajocian, Bathonian and Callovian Stages.
The Dockum is a Late Triassic geologic group found primarily on the Llano Estacado of western Texas and eastern New Mexico with minor exposures in southwestern Kansas, eastern Colorado, and Oklahoma panhandle. The Dockum reaches a maximum thickness of slightly over 650 m but is usually much thinner. The Dockum rests on an unconformity over the Anisian aged Anton Chico Formation.
The Vermejo Formation is a geologic formation of Upper Cretaceous age. It outcrops in the Raton Basin of northeastern New Mexico and southern Colorado.
The Summerville Formation is a geological formation in New Mexico, Colorado, and Utah of the Southwestern United States. It dates back to the Oxfordian stage of the Late Jurassic.
The Pajarito Formation is a geologic formation in eastern New Mexico and west Texas. It preserves fossils dating back to the Albian Age of the Cretaceous Period.
The Bell Ranch Formation is a Late Jurassic (Kimmeridgian) geologic formation in eastern and northeastern New Mexico and the western Oklahoma panhandle. Fossil theropod tracks have been reported from the formation.
The Sloan Canyon Formation is a late Triassic geologic formation exposed in northeastern New Mexico. Fossil theropod tracks have been reported from the formation.
The Mesa Rica Sandstone is a geologic formation in Oklahoma and New Mexico. It preserves fossils dating back to the Cretaceous period.
The Baldy Hill Formation is a geologic formation in northeastern New Mexico and western Oklahoma. It preserves fossils dating back to the late Triassic period.
The Sheep Pen Sandstone is a late Triassic geologic formation exposed in northeastern New Mexico. Fossil theropod tracks have been reported from the formation.
The Travesser Formation is a geologic formation in northeastern New Mexico, southeastern Colorado, westernmost Oklahoma, and northwestern Texas, particularly in the Dry Cimarron valley. It preserves fossils dating back to the late Triassic period.
The Curtis Formation is a geologic formation in Utah. It preserves fossils dating back to the Callovian age of the Jurassic period.
The Lytle Formation or Lytle Sandstone is a geologic formation found in Wyoming, Colorado, and New Mexico.
The Glencairn Formation is a geologic formation found in Colorado and New Mexico. It preserves fossils characteristic of the Albian Age of the Cretaceous Period.
The Romeroville Sandstone is a geologic formation in northeastern New Mexico. It likely was deposited in the Cenomanian Age of the Cretaceous Period.
The Zuni Sandstone is a geologic formation in west-central New Mexico. It marks the southernmost limit of Jurassic fluvial and lacustrine sedimentary formations, which pinch out to leave a single sandstone body.
