| Guavio Formation | |
|---|---|
| Stratigraphic range:Tithonian-Berriasian ~150–140 Ma | |
| Type | Geological formation |
| Unit of | Cáqueza Group |
| Sub-units | Caliza de Las Mercedes Mb. Lutitas de Las Mercedes Mb. Caliza de Malacara Mb. Lutitas de Miralindo Mb. Conglomerado de Miralindo |
| Underlies | Macanal Formation |
| Overlies | Batá Fm.,Girón Fm |
| Thickness | up to 1,000 m (3,300 ft) |
| Lithology | |
| Primary | Conglomerate |
| Other | Limestone,shale |
| Location | |
| Coordinates | 4°59′34.1″N73°28′53.8″W / 4.992806°N 73.481611°W /4.992806; -73.481611 |
| Region | Altiplano Cundiboyacense Eastern Ranges,Andes |
| Country |  Colombia |
| Type section | |
| Named for | Guavio River |
| Named by | Rodríguez & Ulloa |
| Location | Alto de Miralindo,Guateque |
| Year defined | 1976 |
| Coordinates | 4°59′34.1″N73°28′53.8″W / 4.992806°N 73.481611°W /4.992806; -73.481611 |
| Region | Cundinamarca,Boyacá |
| Country | Colombia |
 Paleogeography of Northern South America 150 Ma,by Ron Blakey | |
TheGuavio Formation (Spanish:Calizas del Guavio, Kicg) is ageological formation of theAltiplano Cundiboyacense,Eastern Ranges of theColombianAndes. The formation consists of conglomerates, shales and limestones, dates to theLate Jurassic andEarly Cretaceous periods;Tithonian toBerriasian epochs and has a maximum thickness of 1,000 metres (3,300 ft).
The formation was defined and named in 1976 by Rodríguez and Ulloa after theGuavio River,Cundinamarca.[1]
The Guavio Formation has a maximum thickness of 1,000 metres (3,300 ft), and is characterised by a sequence ofconglomerates,shales andlimestones.[1]
The Guavio Formation, the lowermost unit of theCáqueza Group, overlies theBatá Formation and is overlain by theMacanal Formation. The unit is subdivided into five members, from old to younger; Conglomerado de Miralindo, Lutitas de Miralindo, Caliza de Malacara, Lutitas de Las Mercedes and Caliza de Las Mercedes. The age has been estimated to beTithonian toBerriasian, spanning the Jurassic-Cretaceous boundary. Stratigraphically, the formation is time equivalent with theArcabuco Formation. The formation has been deposited in a shallow marineenvironment in an oxygen-poor basin.[1]
The Guavio Formation is apart from itstype locality at the Alto de Miralindo and Cuchilla de Manizales, found nearGachalá andMedina.[1]
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