Loading AI tools
From Wikipedia, the free encyclopedia
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).
| 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 |
| 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 |
| 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 formation was defined and named in 1991 by Ulloa and Rodríguez after Simijaca, Cundinamarca.[1]
The Simijaca Formation is characterised by a sequence of mudstones, grey and black shales with sandstone and limestone intercalations.[1][2]
The Simijaca Formation conformably overlies the Chiquinquirá Sandstone, and the Hiló and Pacho Formations, and is overlain by the La Frontera Formation.[3] The age has been estimated to be Turonian,[1] or Cenomanian.[4] Stratigraphically, the formation is time equivalent with the Chipaque Formation.[5] The formation has been deposited in an open marine platform setting.[6] The deposition is represented by a maximum flooding surface.[7]
The Simijaca Formation is apart from its type locality in the Quebrada Don Lope,[2] found at surface in the north of the Bogotá savanna, in the Tabio anticlinal, along the road Ubaté-Carmen de Carupa,[8] at the western and eastern flanks of the Aponsentos-Chiquinquirá Synclinal,[9] near Tena, south of Anolaima and Cachipay,[10] and between Anapoima and Granada.[11]
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
