Bandelier Tuff

Bandelier Tuff
Stratigraphic range: Pleistocene, 1.85–1.256 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Kwage Mesa, a typical finger mesa eroded out of the Bandelier Tuff in the Pajarito Plateau
Type	Geologic formation
Unit of	Tewa Group
Sub-units	La Cueva Member, Otowi Member, Tshirege Member
Overlies	Tschicoma Formation, Paliza Canyon Formation
Thickness	330 m (1,080 ft)
Lithology
Primary	Ignimbrite
Other	Pumice
Location
Coordinates	35°45′50″N 106°19′19″W / 35.764°N 106.322°W / 35.764; -106.322
Region	New Mexico
Country	United States
Type section
Named for	Bandelier National Monument
Named by	Harold T.U. Smith
Year defined	1938
Map of Bandelier Tuff exposures

The Bandelier Tuff is a geologic formation exposed in and around the Jemez Mountains of northern New Mexico. It has a radiometric age of 1.85 to 1.25 million years, corresponding to the Pleistocene epoch. The tuff was erupted in a series of at least three caldera eruptions in the central Jemez Mountains.

The Bandelier Tuff was one of the first ignimbrites recognized in the geologic record, and has been extensively studied by geologists seeking to understand the processes involved in volcanic supereruptions.