Bogotá Formation

The Bogotá Formation (Spanish: Formación Bogotá, E_1-2b, Tpb, Pgb) is a geological formation of the Eastern Hills and Bogotá savanna on the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly shale and siltstone formation, with sandstone beds intercalated, dates to the Paleogene period; Upper Paleocene to Lower Eocene epochs, with an age range of 61.66 to 52.5 Ma, spanning the Paleocene–Eocene Thermal Maximum. The thickness of the Bogotá Formation ranges from 169 metres (554 ft) near Tunja to 1,415 metres (4,642 ft) near Bogotá. Fossils of the ungulate Etayoa bacatensis have been found in the Bogotá Formation, as well as numerous reptiles, unnamed as of 2017.

Bogotá Formation
Stratigraphic range: Late Paleocene-Early Eocene (Peligran-Casamayoran) 61.66–52.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Underlies	Regadera Formation
Overlies	Cacho Formation
Thickness	169–1,415 m (554–4,642 ft)
Lithology
Primary	Mudstone, shale, siltstone
Other	Sandstone
Location
Coordinates	4°29′18.4″N 74°08′08.5″W
Region	Bogotá savanna & Eastern Hills, Altiplano Cundiboyacense Eastern Ranges, Andes
Country	Colombia
Type section
Named for	Bogotá
Named by	Hettner
Location	Ciudad Bolívar, Bogotá
Year defined	1892
Coordinates	4°29′18.4″N 74°08′08.5″W
Approximate paleocoordinates	2.1°N 62.4°W / 2.1; -62.4
Region	Cundinamarca
Country	Colombia
Paleogeography of Northern South America 50 Ma, by Ron Blakey

Etymology

The formation was first described by Hettner in 1892,^[1] then by Hubach in 1931, 1945 and 1957, and named in 1963 by Julivert after the Colombian capital Bogotá and its savanna.^[2]

Description

The Bogotá Formation was deposited during the Paleocene–Eocene Thermal Maximum, here indicated as LPTM

Lithologies

The Bogotá Formation consists mainly of grayish-red, locally purplish, commonly greenish-gray, generally poorly stratified mudstone and silty claystone. Lithic arenite sandstone lenses, ranging from fine- to medium-grained, generally friable and variegated, are local constituents. Carbonaceous material is present as thin beds of low-grade argillaceous coal, north of Bogotá.^[3][4] Fossil remains of Etaoya bacatensis, named after Colombian geologist Fernando Etayo and the indigenous name for the Bogotá savanna, Bacatá,^[5] have been found in Ciudad Bolívar, close to the type locality of the Bogotá Formation.^[6] Additionally, macroflora of Palaeophytocrene hammenii, named after Dutch botanist Thomas van der Hammen,^[7] and pollen of Foveotriletes margaritae, Proxapertites operculatus and Foveotricolpites perforatus have been found, used for dating the formation.^[1] Other pollen and flora, as Ulmoideipites krempii, Carpolithus, Anemocardium margaritae, and Hickeycarpum peltatum have been found in the Bogotá Formation.^[8] The abundant paleosols of the Bogotá Formation show an increase in chemical weathering across the Paleocene-Eocene (P-E) transition; the Paleocene–Eocene Thermal Maximum.^[9]

Later analysis has found several other species, such as pleurodire turtles, found at the Doña Juana dump,^[10] dyrosaurid mesoeucrocodylians, boid snakes, dipnoan fishes, frogs, lizards, sebecid crocodyliforms and 11 fossils of mammals.^[11] The find of a derived snake in the Lower Eocene section of the formation represents the oldest New World record.^[12] The finds of iguanians, including the fossil record of hoplocercines, and boine, caenophidian, and ungaliophiine snakes, indicate a tropical forest environment, present just before the Early Eocene Climatic Optimum (EECO).^[13] The faunal distribution has been correlated to the Carodnia-, Amphidolops-, and Wainka-bearing Peñas Coloradas Formation of the Golfo San Jorge Basin in Patagonia, Argentina.^[14]

Stratigraphy and depositional environment

The Bogotá Formation, with a thickness of 169 metres (554 ft) close to Tunja to 1,415 metres (4,642 ft) near Bogotá,^[15][16] overlies the Cacho Formation and is overlain by the Regadera Formation. The age has been estimated to be Late Paleocene to Early Eocene.^[17] The middle part of the succession has been dated using detrital zircons at 56.2 ± 1.6 Ma.^[3][18] The spread of ages based on zircons has been reported from 60.96 ± 0.7 to 53.6 ± 1.1 Ma.^[19] The Bogotá Formation is laterally equivalent with the shales of the Socha Formation, the San Fernando Formation, the El Limbo Formation,^[17] Los Cuervos Formation,^[20] and the fossil-rich Cerrejón Formation of La Guajira.^[11]

Outcrops

Type locality of the Bogotá Formation in the south of the Bogotá savanna

The Bogotá Formation is apart from its type locality, found in the synclinals of the Río Frío, Checua-Lenguazaque, Sesquilé, Sisga, Subachoque,^[21] around Lake Suesca, in the Tenza Valley, and in the synclinals of Teusacá and Usme.^[2][22][23] In the Usme Synclinal, the formation has a thickness of 436.5 metres (1,432 ft).^[24] The campus of the Universidad La Javeriana has the Bogotá Formation as solid basement rock.^[25]

The Bogotá Formation forms the footwall of the eastward compressional Chicamocha Fault,^[21] and the footwall of the westward thrusting Bogotá Fault.^[22]

Regional correlations

Stratigraphy of the Llanos Basin and surrounding provinces

Ma	Age	Paleomap	Regional events	Catatumbo	Cordillera	proximal Llanos	distal Llanos	Putumayo	VSM	Environments	Maximum thickness	Petroleum geology	Notes
0.01	Holocene		Holocene volcanism Seismic activity	alluvium								Overburden
1	Pleistocene		Pleistocene volcanism Andean orogeny 3 Glaciations	Guayabo	Soatá Sabana	Necesidad	Guayabo	Gigante Neiva		Alluvial to fluvial (Guayabo)	550 m (1,800 ft) (Guayabo)		[26][27][28][29]
2.6	Pliocene		Pliocene volcanism Andean orogeny 3 GABI		Subachoque
5.3	Messinian		Andean orogeny 3 Foreland		Marichuela			Caimán	Honda				[28][30]
13.5	Langhian		Regional flooding	León	hiatus	Caja	León			Lacustrine (León)	400 m (1,300 ft) (León)	Seal	[29][31]
16.2	Burdigalian		Miocene inundations Andean orogeny 2	C1		Carbonera C1		Ospina		Proximal fluvio-deltaic (C1)	850 m (2,790 ft) (Carbonera)	Reservoir	[30][29]
17.3				C2		Carbonera C2				Distal lacustrine-deltaic (C2)		Seal
19				C3		Carbonera C3				Proximal fluvio-deltaic (C3)		Reservoir
21	Early Miocene		Pebas wetlands	C4		Carbonera C4			Barzalosa	Distal fluvio-deltaic (C4)		Seal
23	Late Oligocene		Andean orogeny 1 Foredeep	C5		Carbonera C5		Orito		Proximal fluvio-deltaic (C5)		Reservoir	[27][30]
25				C6		Carbonera C6				Distal fluvio-lacustrine (C6)		Seal
28	Early Oligocene			C7		C7		Pepino	Gualanday	Proximal deltaic-marine (C7)		Reservoir	[27][30][32]
32	Oligo-Eocene			C8	Usme	C8	onlap			Marine-deltaic (C8)		Seal Source	[32]
35	Late Eocene			Mirador		Mirador				Coastal (Mirador)	240 m (790 ft) (Mirador)	Reservoir	[29][33]
40	Middle Eocene				Regadera				hiatus
45
50	Early Eocene			Socha		Los Cuervos				Deltaic (Los Cuervos)	260 m (850 ft) (Los Cuervos)	Seal Source	[29][33]
55	Late Paleocene		PETM 2000 ppm CO2	Los Cuervos	Bogotá				Gualanday
60	Early Paleocene		SALMA	Barco	Guaduas	Barco		Rumiyaco		Fluvial (Barco)	225 m (738 ft) (Barco)	Reservoir	[26][27][30][29][34]
65	Maastrichtian		KT extinction	Catatumbo	Guadalupe				Monserrate	Deltaic-fluvial (Guadalupe)	750 m (2,460 ft) (Guadalupe)	Reservoir	[26][29]
72	Campanian		End of rifting	Colón-Mito Juan									[29][35]
83	Santonian							Villeta/Güagüaquí
86	Coniacian
89	Turonian		Cenomanian-Turonian anoxic event	La Luna	Chipaque	Gachetá	hiatus			Restricted marine (all)	500 m (1,600 ft) (Gachetá)	Source	[26][29][36]
93	Cenomanian		Rift 2
100	Albian				Une	Une		Caballos		Deltaic (Une)	500 m (1,600 ft) (Une)	Reservoir	[30][36]
113	Aptian			Capacho	Fómeque			Motema	Yaví	Open marine (Fómeque)	800 m (2,600 ft) (Fómeque)	Source (Fóm)	[27][29][37]
125	Barremian		High biodiversity	Aguardiente	Paja					Shallow to open marine (Paja)	940 m (3,080 ft) (Paja)	Reservoir	[26]
129	Hauterivian		Rift 1	Tibú- Mercedes	Las Juntas	hiatus				Deltaic (Las Juntas)	910 m (2,990 ft) (Las Juntas)	Reservoir (LJun)	[26]
133	Valanginian			Río Negro	Cáqueza Macanal Rosablanca					Restricted marine (Macanal)	2,935 m (9,629 ft) (Macanal)	Source (Mac)	[27][38]
140	Berriasian			Girón
145	Tithonian		Break-up of Pangea	Jordán	Arcabuco	Buenavista Batá		Saldaña		Alluvial, fluvial (Buenavista)	110 m (360 ft) (Buenavista)	"Jurassic"	[30][39]
150	Early-Mid Jurassic		Passive margin 2	La Quinta	Montebel Noreán	hiatus				Coastal tuff (La Quinta)	100 m (330 ft) (La Quinta)		[40]
201	Late Triassic			Mucuchachi				Payandé					[30]
235	Early Triassic		Pangea		hiatus							"Paleozoic"
250	Permian
300	Late Carboniferous		Famatinian orogeny						Cerro Neiva ()				[41]
340	Early Carboniferous		Fossil fish Romer's gap		Cuche (355-385)	Farallones ()				Deltaic, estuarine (Cuche)	900 m (3,000 ft) (Cuche)
360	Late Devonian		Passive margin 1	Río Cachirí (360-419)					Ambicá ()	Alluvial-fluvial-reef (Farallones)	2,400 m (7,900 ft) (Farallones)		[38][42][43][44][45]
390	Early Devonian		High biodiversity	Floresta (387-400) El Tíbet						Shallow marine (Floresta)	600 m (2,000 ft) (Floresta)
410	Late Silurian		Silurian mystery
425	Early Silurian			hiatus
440	Late Ordovician		Rich fauna in Bolivia	San Pedro (450-490)		Duda ()
470	Early Ordovician		First fossils		Busbanzá (>470±22) Chuscales Otengá	Guape ()		Río Nevado ()	Hígado () Agua Blanca Venado (470-475)				[46][47][48]
488	Late Cambrian		Regional intrusions	Chicamocha (490-515)	Quetame ()	Ariarí ()		SJ del Guaviare (490-590)	San Isidro ()				[49][50]
515	Early Cambrian		Cambrian explosion										[48][51]
542	Ediacaran		Break-up of Rodinia		pre-Quetame		post-Parguaza		El Barro ()	Yellow: allochthonous basement (Chibcha terrane) Green: autochthonous basement (Río Negro-Juruena Province)		Basement	[52][53]
600	Neoproterozoic		Cariri Velhos orogeny	Bucaramanga (600-1400)				pre-Guaviare					[49]
800			Snowball Earth										[54]
1000	Mesoproterozoic		Sunsás orogeny			Ariarí (1000)			La Urraca (1030-1100)				[55][56][57][58]
1300			Rondônia-Juruá orogeny			pre-Ariarí	Parguaza (1300-1400)		Garzón (1180-1550)				[59]
1400				pre-Bucaramanga									[60]
1600	Paleoproterozoic						Maimachi (1500-1700)		pre-Garzón				[61]
1800			Tapajós orogeny				Mitú (1800)						[59][61]
1950			Transamazonic orogeny				pre-Mitú						[59]
2200			Columbia
2530	Archean		Carajas-Imataca orogeny										[59]
3100			Kenorland
Sources

Legend

• group
• important formation
• fossiliferous formation
• minor formation
• (age in Ma)
• proximal Llanos (Medina)^{[note 1]}
• distal Llanos (Saltarin 1A well)^{[note 2]}

Itaboraian correlations

Itaboraian correlations in South America

Formation	Itaboraí	Las Flores	Koluel Kaike	Maíz Gordo	Muñani	Mogollón	Bogotá	Cerrejón	Ypresian (IUCS) • Wasatchian (NALMA) Bumbanian (ALMA) • Mangaorapan (NZ)
Basin	Itaboraí	Golfo San Jorge		Salta	Altiplano Basin	Talara & Tumbes	Altiplano Cundiboyacense	Cesar-Ranchería	Bogotá Formation (South America)
Country	Brazil	Argentina			Peru		Colombia
Carodnia
Gashternia
Henricosbornia
Victorlemoinea
Polydolopimorphia
Birds
Reptiles
Fish
Flora
Environments	Alluvial-lacustrine	Alluvial-fluvial		Fluvio-lacustrine	Lacustrine	Fluvial	Fluvio-deltaic		Itaboraian volcanoclastics Itaboraian fauna Itaboraian flora
Volcanic			Yes

See also

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