Trincheras Formation | |
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Stratigraphic range: Early Aptian ~ | |
Type | Geological formation |
Unit of | Villeta Group |
Sub-units | Anapoima Mb., El Tigre Mb. |
Underlies | Socotá Fm., El Peñón Fm. |
Overlies | Murca Fm., La Naveta Fm., Útica Fm. |
Thickness | up to 1,260 m (4,130 ft) |
Lithology | |
Primary | Shale |
Other | Sandstone, limestone |
Location | |
Coordinates | 4°30′13″N 74°36′22″W / 4.50361°N 74.60611°W |
Region | Altiplano Cundiboyacense Eastern Ranges, Andes |
Country | Colombia |
Type section | |
Named for | Quebrada Trincheras |
Named by | Cáceres & Etayo |
Location | Apulo |
Year defined | 1969 |
Coordinates | 4°30′13″N 74°36′22″W / 4.50361°N 74.60611°W |
Region | Cundinamarca |
Country | Colombia |
Paleogeography of Northern South America 120 Ma, by Ron Blakey |
The Trincheras Formation (Spanish: Formación Trincheras, Kitr) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consisting of a lower unit of calcareous shales and an upper sequence of shales dates to the Early Cretaceous period; Early Aptian epoch and has a maximum thickness of 1,260 metres (4,130 ft). The formation, deposited in a marine platform environment, part of a transgressive cycle, hosts ammonite, bryozoan, mollusc and echinoid fossils.