Macanal Formation
| Macanal Formation | |
|---|---|
| Stratigraphic range: Berriasian-Valanginian ~ | |
Outcrop of the Macanal Formation along the road between Bogotá and Villavicencio | |
| Type | Geological formation |
| Unit of | Cáqueza Group |
| Underlies | Las Juntas Formation |
| Overlies | Guavio Fm., Santa Rosa Fm., Ubalá Fm., Chivor Fm., Batá Fm. |
| Thickness | up to 2,935 m (9,629 ft) |
| Lithology | |
| Primary | Organic shale |
| Other | Limestone, gypsum, emeralds |
| Location | |
| Coordinates | 4°58′19″N 73°19′10″W / 4.97194°N 73.31944°W |
| Region | Altiplano Cundiboyacense & Tenza Valley Eastern Ranges Andes |
| Country | Colombia |
| Type section | |
| Named for | Macanal |
| Named by | Rodríguez & Ulloa |
| Location | Macanal |
| Year defined | 1979 |
| Coordinates | 4°58′19″N 73°19′10″W / 4.97194°N 73.31944°W |
| Region | Boyacá |
| Country | Colombia |
The Macanal Formation or Macanal Shale (Spanish: (Formación) Lutitas de Macanal, Kilm, K1m) is a fossiliferous geological formation of the Altiplano Cundiboyacense and Tenza Valley in the Eastern Ranges of the Colombian Andes. The predominantly organic shale formation dates to the Early Cretaceous period; Berriasian to Valanginian epochs and has a maximum thickness of 2,935 metres (9,629 ft). The Macanal Formation contains numerous levels of fossiliferous abundances. Bivalves, ammonites and fossil flora have been found in the formation.
The formation is a source rock for oil and gas in the Eastern Cordillera Basin and adjacent Llanos Basin foothills and provides emeralds in the vicinity of Macanal, after which the formation is named.