Moenkopi Formation

Moenkopi Formation
Stratigraphic range: Early Triassic–Middle Triassic PreꞒ Ꞓ O S D C P T J K Pg N
Moenkopi at its reference section along the Little Colorado River west of Cameron, Arizona
Type	Geological formation
Sub-units	See "Members" section
Underlies	Chinle Formation
Overlies	Kaibab Limestone
Lithology
Primary	Sandstone
Other	Shale
Location
Coordinates	35°55′05″N 111°29′20″W / 35.918°N 111.489°W / 35.918; -111.489
Region	Northern Arizona Southeast California East-central Nevada Southern Utah Northwestern New Mexico Southwestern Colorado
Country	Southwestern United States
Type section
Named for	Moenkopi Wash
Named by	Ward
Year defined	1901
Moenkopi Formation (the United States) Show map of the United States Moenkopi Formation (Arizona) Show map of Arizona

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^[1] and possibly part of the Middle Triassic, around 240 million years ago.^[2]