Fómeque Formation

Fómeque Formation
Stratigraphic range: Barremian-Late Aptian
~126–113 Ma
Type Geological formation
Unit of Villeta Group
Underlies Une Formation
Overlies Las Juntas Formation
Thickness up to 1,200 m (3,900 ft)
Lithology
Primary Organic shale
Other Limestone, sandstone
Location
Coordinates 4°27′07″N 74°03′20″W / 4.45194°N 74.05556°W / 4.45194; -74.05556Coordinates: 4°27′07″N 74°03′20″W / 4.45194°N 74.05556°W / 4.45194; -74.05556
Region Altiplano Cundiboyacense
Eastern Ranges, Andes
Country  Colombia
Type section
Named for Fómeque
Named by Hubach
Location Fómeque
Year defined 1957
Coordinates 4°27′07″N 74°03′20″W / 4.45194°N 74.05556°W / 4.45194; -74.05556
Region Cundinamarca, Boyacá
Country  Colombia

Paleogeography of Northern South America
120 Ma, by Ron Blakey

The Fómeque Formation (Spanish: Formación Fómeque, Kif) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly organic shale formation dates to the Early Cretaceous period; Barremian to Late Aptian epochs and has a maximum thickness of 1,200 metres (3,900 ft).

Etymology

The formation was defined and named in 1957 by Hubach after Fómeque, Cundinamarca.[1]

Description

Lithologies

The Fómeque Formation has a maximum thickness of 1,200 metres (3,900 ft), and is characterised by a sequence of pyritic organic shales, with limestones and sandstone banks intercalated in the formation. The Fómeque Formation contains high values of TOC.[2] Fossils of Acarthohoplites sp., Melchionites sp., Nicklesia sp., Olcostephanus sp., Pulchellia sp. have been found in the formation.[3]

Stratigraphy and depositional environment

The Fómeque Formation overlies the Las Juntas Formation and is overlain by the Une Formation. The age has been estimated to be Barremian to Late Aptian. Stratigraphically, the formation is time equivalent with the Mercedes Formation. The formation has been deposited in a shallow marine environment.[2]

Outcrops

Type locality of the Fómeque Formation to the southeast of the Bogotá savanna

The Fómeque Formation is apart from its type locality, found in other parts of the Eastern Ranges.

Regional correlations

Cretaceous stratigraphy of the central Colombian Eastern Ranges
AgePaleomapVMMGuaduas-VélezW Emerald BeltVilleta anticlinalChiquinquirá-
Arcabuco		Tunja-
Duitama		Altiplano CundiboyacenseEl Cocuy
MaastrichtianUmir Fm.Córdoba Fm.Seca Fm.erodedGuadalupe Gp.Colón-Mito Juan Fm.
Umir Fm.
CampanianCórdoba Fm.
Oliní Gp.
SantonianLa Luna Fm.Cimarrona Fm. - La Tabla Fm.La Luna Fm.
ConiacianOliní Gp.Conejo Fm.Chipaque Fm.
Güagüaquí Gp
Loma Gorda Fm.undefinedLa Frontera Fm.
TuronianHondita Fm.La Frontera Fm.Otanche Fm.
CenomanianSimití Fm.hiatusLa Corona Gb.Simijaca Fm.Capacho Fm.
Pacho Fm.Hiló Fm. - Pacho Fm.Churuvita Fm.Une Fm.Aguardiente Fm.
AlbianHiló Fm.Chiquinquirá Sst.Tibasosa Fm.Une Fm.
Tablazo Fm.Tablazo Fm.Capotes Fm. - La Palma Fm. - Simití Fm.Simití Fm.Tibú-Mercedes Fm.
AptianCapotes Fm.Socotá Fm. - El Peñón Fm.Paja Fm.Fómeque Fm.
Paja Fm.Paja Fm.El Peñón Fm.Trincheras Fm.Río Negro Fm.
La Naveta Fm.
Barremian
HauterivianMuzo Fm.
Cáqueza Gp
Las Juntas Fm.
Rosablanca Fm.Ritoque Fm.
ValanginianRitoque Fm.Furatena Fm.Útica Fm. - Murca Fm.Rosablanca Fm.Girón Fm.Macanal Fm.
Rosablanca Fm.
BerriasianCumbre Fm.Cumbre Fm.Los Medios Fm.Guavio Fm.
Tambor Fm.Arcabuco Fm.Cumbre Fm.
Sources

See also

Geology of the Eastern Hills
Geology of the Ocetá Páramo
Geology of the Altiplano Cundiboyacense

References

  1. ↑ Acosta & Ulloa, 2002, p.52
  2. 1 2 Acosta & Ulloa, 2002, p.53
  3. ↑ Caicedo et al., 2002, p.29

Bibliography

Maps

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.