Nacimiento Formation

Nacimiento Formation
Stratigraphic range: Paleocene
~
The badlands below Angel Peak are made up of Nacimiento Formation rocks
TypeFormation
UnderliesSan Jose Formation
OverliesOjo Alamo Formation
Thickness254 m (833 ft)
Lithology
PrimaryShale
OtherSiltstone, sandstone
Location
Coordinates36°00′46″N 106°59′08″W / 36.0126977°N 106.9855481°W / 36.0126977; -106.9855481
RegionNew Mexico
CountryUnited States
Type section
Named forNacimiento (now Cuba, New Mexico)
Named byJ.H. Gardner
Year defined1910
Nacimiento Formation (the United States)
Nacimiento Formation (New Mexico)

The Nacimiento Formation is a sedimentary rock formation in the San Juan Basin of western New Mexico (United States). It is dated to approximately 61.0–65.7 million years ago, corresponding to the early and middle Paleocene. The formation has yielded numerous fossil assemblages from the interval following the Cretaceous–Paleogene extinction event, which have been used to study biotic recovery and the early diversification of mammals after the extinction.