Regadera Formation
{{short description|Geological formation of the Colombian Andes}}
{{Infobox rockunit
| name = Regadera Formation
| period = Eocene
| age = Middle to Late Eocene
~{{fossil range|47|40}}
| image =
| imagesize =
| caption =
| type = Geological formation
| prilithology = Sandstone, conglomerate
| otherlithology = Shale
| unitof =
| subunits =
| underlies = Usme Fm., Tilatá Fm.
| overlies = Bogotá Formation
| thickness = up to {{convert|756|m|ft|-1}}
| area =
| map = Blakey 050Ma - COL.jpg
| map_caption = Paleogeography of Northern South America
50 Ma, {{small|by Ron Blakey}}
| location =
| coordinates = {{coord|4|23|30.8|N|74|08|26.3|W|display=inline,title}}
| region = Bogotá savanna, Altiplano Cundiboyacense
Eastern Ranges, Andes
| country = Colombia
| extent =
| namedfor = La Regadera Reservoir
| namedby = Julivert
| year_ts = 1963
| coordinates_ts = {{coord|4|23|30.8|N|74|08|26.3|W|display=inline}}
| paleocoordinates_ts =
| region_ts = Cundinamarca
| country_ts = Colombia
| thickness_ts =
}}
The Regadera Formation ({{langx|es|Formación Regadera}}, E2r, Tpr) is a geological formation of the Bogotá savanna, Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly sandstone and conglomeratic formation, with pink shale beds intercalated, dates to the Paleogene period; Middle to Late Eocene epoch, and has a maximum thickness of {{convert|765|m|ft}}.
Etymology
The formation was first described by Hubach in 1931 as part of the Usme Formation and redefined and named in 1963 by Julivert after the La Regadera Reservoir.Montoya & Reyes, 2005, p.60
Description
= Lithologies =
The Regadera Formation consists mainly of quartz arenitic sandstone and conglomerates with some shale beds.Bayona et al., 2010, p.5
= Stratigraphy and depositional environment =
The Regadera Formation overlies the Bogotá Formation and is overlain by the Usme and Tilatá Formations. The age has been estimated, based on palynological data of Echitriporites trianguliformis var. orbicularis, Nothofagidites sp. and Multiporopollenites pauciporatus, to be Middle to Late Eocene.Montoya & Reyes, 2005, p.64 The depositional environment has been interpreted as a braided river setting.Bayona et al., 2010, p.7
Outcrops
{{Location map | Bogotá savanna
| width = 250
| lat_deg = 4.391876
| lon_deg = -74.140632
| label =
| float = left
| position = right
| mark = Orange pog.svg
| marksize = 12
| caption = Type locality of the Regadera Formation to the south of the Bogotá savanna
}}
The Regadera Formation is apart from its type locality in the synclinal of Usme, the valley of the Tunjuelo River, found in the synclinal of Sisga. In the Tunjuelo River valley, the Regadera Formations is present in the escarpments on the river banks.Bayona et al., 2010, p.11
{{clear}}
Regional correlations
{{Stratigraphy of the Llanos Basin}}
See also
: {{icon|GAN}} Geology of the Eastern Hills
: {{icon|B}} Geology of the Ocetá Páramo
: {{icon|C}} Geology of the Altiplano Cundiboyacense
Notes and references
= Notes =
{{reflist|group=note}}
= References =
{{reflist|20em}}
= Bibliography =
- {{citation |last1=Bayona |first1=Germán |last2=Montenegro |first2=Omar |last3=Cardona |first3=Agustín |last4=Jaramillo |first4=Carlos |last5=Lamus |first5=Felipe |last6=Morón |first6=Sara |last7=Quiroz |first7=Luiz |last8=Ruíz |first8=María C. |last9=Valencia and Mauricio Parra |first9=Victor |year=2010 |title=Estratigrafía, procedencia, subsidencia y exhumación de las unidades paleógenas en el Sinclinal de Usme, sur de la zona axial de la Cordillera Oriental - Stratigraphy, provenance, subsidence and exhumation of the Paleogene succession in the Usme Syncline, southern axial zone of the Eastern Cordillera |url=http://www.bdigital.unal.edu.co/24001/1/21100-118170-1-PB.pdf |journal=Geología Colombiana |volume=35 |pages=5–35 |accessdate=2017-03-16}}
- {{citation |last1=Montoya Arenas |first1=Diana María |last2=Reyes Torres |first2=Germán Alfonso |year=2005 |title=Geología de la Sabana de Bogotá |publisher=INGEOMINAS |pages=1–104}}
== Maps ==
- {{citation |last1=Fuquen M. |first1=Jaime A |last2=Osorno M |first2=José F. |year=2009 |title=Plancha 190 - Chiquinquirá - 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QVEYzMnV1ekNxTDQ |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
- {{citation |last1=Ulloa |first1=Carlos |last2=Acosta |first2=Jorge |year=1998 |title=Plancha 208 - Villeta - 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QMjhLeWJ0aU1Za1U |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
- {{citation |last1=Montoya |first1=Diana María |last2=Reyes |first2=Germán |year=2009 |title=Plancha 209 - Zipaquirá - 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QYUdHRWFiN1JrVms |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
- {{citation |last1=Buitrago |first1=José Alberto |last2=Terraza M. |first2=Roberto |author3-link=Fernando Etayo |last3=Etayo |first3=Fernando |year=1998 |title=Plancha 228 - Santafé de Bogotá Noreste - 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QTlNraVVZZ2ZCY0E |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
- {{citation |last1=Acosta |first1=Jorge E. |last2=Ulloa |first2=Carlos E. |year=1998 |title=Plancha 246 - Fusagasugá - 1:100,000 |url=https://drive.google.com/open?id=0BwFQPMJEi17QNkY5UEloZU9pdEk |publisher=INGEOMINAS |pages=1 |accessdate=2017-06-06}}
External links
- {{citation |last1=Gómez |first1=J. |last2=Montes |first2=N.E. |last3=Nivia |first3=Á. |last4=Diederix |first4=H. |year=2015 |title=Plancha 5-09 del Atlas Geológico de Colombia 2015 – escala 1:500,000 |url=https://www.researchgate.net/publication/309533589 |publisher=Servicio Geológico Colombiano |pages=1 |accessdate=2017-03-16}}
Category:Geologic formations of Colombia
Category:Eocene Series of South America
Category:Conglomerate formations