| Pilar Formation | |
|---|---|
| Stratigraphic range: | |
 Pilar Formation carbonaceous phyllite beds near Pilar, New Mexico. | |
| Type | Formation |
| Unit of | Trampas Group |
| Underlies | Piedra Lumbre Formation |
| Overlies | Rinconada Formation |
| Thickness | 700 m (2,300 ft) |
| Lithology | |
| Primary | Phyllite |
| Other | Schist |
| Location | |
| Coordinates | 36°12′40″N 105°49′37″W / 36.211°N 105.827°W |
| Region | Picuris Mountains, New Mexico |
| Country | United States |
| Type section | |
| Named for | Pilar, New Mexico |
| Named by | Montgomery |
| Year defined | 1953 |
  Pilar Formation (the United States)  Pilar Formation (New Mexico) | |
The Pilar Formation is a geologic formation that crops out in the Picuris Mountains of northern New Mexico. It has a radiometric age of 1488 ± 6 million years, corresponding to the Calymmian period.