| Simijaca Formation | |
|---|---|
| Stratigraphic range: Cenomanian-Turonian ~ | |
| Type | Geological formation |
| Unit of | Villeta Group |
| Underlies | La Frontera Formation |
| Overlies | Chiquinquirá Sst., Churuvita Fm., Hiló Fm., Pacho Fm. |
| Thickness | up to 693 m (2,270 ft) |
| Lithology | |
| Primary | Mudstone |
| Other | Shale, sandstone, limestone |
| Location | |
| Coordinates | 5°29′15″N 73°50′55″W / 5.48750°N 73.84861°W |
| Region | Altiplano Cundiboyacense Eastern Ranges, Andes |
| Country |  Colombia |
| Type section | |
| Named for | Simijaca |
| Named by | Ulloa & Rodríguez |
| Location | South of Simijaca |
| Year defined | 1991 |
| Coordinates | 5°29′15″N 73°50′55″W / 5.48750°N 73.84861°W |
| Region | Cundinamarca, Boyacá |
| Country | Colombia |
| Thickness at type section | 432 metres (1,420 ft) |
 Paleogeography of Northern South America 90 Ma, by Ron Blakey | |
The Simijaca Formation (Spanish: Formación Simijaca, K2S, Kss) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly mudstone formation dates to the Late Cretaceous period; Turonian and Cenomanian epochs, and has a maximum thickness of 693 metres (2,274 ft).