| El Peñón Formation | |
| Period: | Aptian |
| Age: | Late Aptian ~ |
| Type: | Geological formation |
| Prilithology: | Calcareous shale |
| Otherlithology: | Siltstone, gypsum |
| Unitof: | Villeta Group |
| Underlies: | Capotes Formation |
| Overlies: | Trincheras Formation |
| Thickness: | more than 381m (1,250feet) |
| Map: | Blakey 120Ma - COL.jpg |
| Coordinates: | 5.2536°N -74.3411°W |
| Region: | Altiplano Cundiboyacense Eastern Ranges, Andes |
| Namedfor: | El Peñón |
| Namedby: | Ulloa |
| Year Ts: | 1982 |
| Location Ts: | El Peñón |
| Coordinates Ts: | 5.2536°N -74.3411°W |
| Region Ts: | Cundinamarca |
| Thickness Ts: | 381m (1,250feet) |
The El Peñón Formation (Spanish; Castilian: Formación El Peñón, Kipe) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consists of calcareous shales and siltstones and dates to the Early Cretaceous period; Late Aptian epoch and has a measured thickness at its type section of 381m (1,250feet). Ammonite fossils have been found in the formation, deposited in a shallow marine platform environment.
The formation was defined and named in 1982 by Ulloa after El Peñón, Cundinamarca.
The El Peñón Formation has at is type section a thickness of 381m (1,250feet), and is characterised by a sequence of calcareous shales and siltstones. The middle part of the sequence contains gypsum.[1] Fossils of the ammonites Cheloniceras sp. and Epicheloniceras sp. aff. carlosacostai have been found in the El Peñón Formation.[2]
The El Peñón Formation, part of the Villeta Group, conformably overlies the Trincheras Formation and is conformably overlain by the Capotes Formation.[3] The age has been estimated to be Late Aptian.[2] Stratigraphically, the formation is time equivalent with the Tablazo Formation and a lateral facies equivalent of the Socotá Formation.[4] The formation has been deposited in a shallow marine platform environment.[2] In the Late Aptian, central Colombia was dominated by shallow marine carbonate platform environments.[5]
The El Peñón Formation, restricted to Cundinamarca, is locally found around its type locality,[2] between Bituima and Guayabal de Síquima,[6] and along the road from Villeta to Sasaima.[7]
Geology of the Eastern Hills
Geology of the Ocetá Páramo
Geology of the Altiplano Cundiboyacense