Macanal Formation

The formation was defined and named in 1979 by Rodríguez and Ulloa after Macanal, Cundinamarca.^[1][2] The name Macanal is either derived from the Muysccubun word Macana, meaning garrote, or from the Macana palm tree.^[3][4]

The Macanal Formation has a maximum thickness of 2,935 metres (9,629 ft), and is characterised by a sequence of micaceous organic shales,^[2] with calcite veins and gypsum occurrences intercalated in the formation. The Macanal Formation contains high values of TOC.^[5] In the Eastern Cordillera Basin and the adjacent foothills of the Llanos Basin, the Macanal Formation is a source rock for oil and gas.^[6] In the vicinity of Macanal, the formation provides emeralds.^[7][8]

The Macanal Formation, a unit of the Cáqueza Group, concordantly overlies the Guavio, Santa Rosa, Ubalá, Chivor and Batá Formations,^[9] and is concordantly overlain by the Las Juntas Formation. The age has been estimated to be Berriasian to Valanginian. Stratigraphically, the formation is time equivalent with the Mercedes, Tambor, Rosablanca, Murca and La Naveta Formations.^[10] The formation has been deposited in a shallow marine environment in an enclosed basin,^[5] with as provenance areas the Santander High and the Guiana Shield.^[11] The Macanal Formation is part of the syn-rift sequence of eastern Colombia.^[12]

The Macanal Formation contains numerous levels of fossiliferous abundances. Bivalves, ammonites and flora have been found in the formation.^[13] Ammonites of Substeueroceras cf. mutabile, Sarasinella cf. hondana, Subalpinites sp., Berriasela sp., Neocomites cf. wichmanni, Olcostephanus sp., Olcostephanus cf. atherstoni, Favrella cf. colombiana, Acanthodiscus sp. have been registered in the formation, as well as bivalves of Corbis (Sphaera) cf. corrugata, Trigonia cf. hondana, Trigonia (Buchotrigonia) cf. abrupta, Trigonia (Notoscabrotrigonia) cf. tocaimaana, and Exogyra cf. boussingaulti.^[14] Analysis of the deformation registered in ammonite fossils has helped in understanding the tectonic history of the Llanos foothills of the Eastern Ranges.^[15]

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Type locality of the Macanal Formation in the Tenza Valley to the east of the Altiplano Cundiboyacense

The Macanal Formation is apart from its type locality in the Batá River canyon,^[16][17] found in the Cravo Sur anticline, east of the Ocetá Páramo,^[18] in the Desespero Synclinal in the southern and northern parts of Labranzagrande,^[19][20] around Páez and Campohermoso,^[17] in the eastern part of Gama, bordering the Guavio Reservoir,^[21] and in the Servitá Synclinal, west of Villavicencio.^[22] The Macanal Formation crops out along the road between Bogotá and Villavicencio and is there heavily fractured and folded. The Macanal Formation is the most extensive formation around Cáqueza,^[23] and Gachalá, Cundinamarca.^[24]

The Pajarito Fault thrusts the Macanal Formation on top of the Fómeque Formation to the east of Lake Tota,^[25] and the Chámeza Fault thrusts the Macanal Formation on top of the overlying Las Juntas Formation around Chámeza, Casanare.^[26] The Ubaque Fault forms the contact between the Fómeque Formation and the Macanal Formation,^[27] while the Las Mercedes Fault puts the Quetame Group in contact with the Macanal Formation near Quetame,^[28] as does the San Juanito Fault.^[29] The Servitá Fault forms the contact between the Guatiquía Redbeds and the Macanal Formation,^[30] and the Upín Fault, part of the same system puts the Macanal Formation in contact with the Tertiary Palmichal Group.^[31] At this contact, brines are extracted from the formation.^[32]

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)		[33][34][35][36]
2.6	Pliocene		Pliocene volcanism Andean orogeny 3 GABI		Subachoque
5.3	Messinian		Andean orogeny 3 Foreland		Marichuela			Caimán	Honda				[35][37]
13.5	Langhian		Regional flooding	León	hiatus	Caja	León			Lacustrine (León)	400 m (1,300 ft) (León)	Seal	[36][38]
16.2	Burdigalian		Miocene inundations Andean orogeny 2	C1		Carbonera C1		Ospina		Proximal fluvio-deltaic (C1)	850 m (2,790 ft) (Carbonera)	Reservoir	[37][36]
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	[34][37]
25				C6		Carbonera C6				Distal fluvio-lacustrine (C6)		Seal
28	Early Oligocene			C7		C7		Pepino	Gualanday	Proximal deltaic-marine (C7)		Reservoir	[34][37][39]
32	Oligo-Eocene			C8	Usme	C8	onlap			Marine-deltaic (C8)		Seal Source	[39]
35	Late Eocene			Mirador		Mirador				Coastal (Mirador)	240 m (790 ft) (Mirador)	Reservoir	[36][40]
40	Middle Eocene				Regadera				hiatus
45
50	Early Eocene			Socha		Los Cuervos				Deltaic (Los Cuervos)	260 m (850 ft) (Los Cuervos)	Seal Source	[36][40]
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	[33][34][37][36][41]
65	Maastrichtian		KT extinction	Catatumbo	Guadalupe				Monserrate	Deltaic-fluvial (Guadalupe)	750 m (2,460 ft) (Guadalupe)	Reservoir	[33][36]
72	Campanian		End of rifting	Colón-Mito Juan									[36][42]
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	[33][36][43]
93	Cenomanian		Rift 2
100	Albian				Une	Une		Caballos		Deltaic (Une)	500 m (1,600 ft) (Une)	Reservoir	[37][43]
113	Aptian			Capacho	Fómeque			Motema	Yaví	Open marine (Fómeque)	800 m (2,600 ft) (Fómeque)	Source (Fóm)	[34][36][44]
125	Barremian		High biodiversity	Aguardiente	Paja					Shallow to open marine (Paja)	940 m (3,080 ft) (Paja)	Reservoir	[33]
129	Hauterivian		Rift 1	Tibú- Mercedes	Las Juntas	hiatus				Deltaic (Las Juntas)	910 m (2,990 ft) (Las Juntas)	Reservoir (LJun)	[33]
133	Valanginian			Río Negro	Cáqueza Macanal Rosablanca					Restricted marine (Macanal)	2,935 m (9,629 ft) (Macanal)	Source (Mac)	[34][45]
140	Berriasian			Girón
145	Tithonian		Break-up of Pangea	Jordán	Arcabuco	Buenavista Batá		Saldaña		Alluvial, fluvial (Buenavista)	110 m (360 ft) (Buenavista)	"Jurassic"	[37][46]
150	Early-Mid Jurassic		Passive margin 2	La Quinta	Montebel Noreán	hiatus				Coastal tuff (La Quinta)	100 m (330 ft) (La Quinta)		[47]
201	Late Triassic			Mucuchachi				Payandé					[37]
235	Early Triassic		Pangea		hiatus							"Paleozoic"
250	Permian
300	Late Carboniferous		Famatinian orogeny						Cerro Neiva ()				[48]
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)		[45][49][50][51][52]
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)				[53][54][55]
488	Late Cambrian		Regional intrusions	Chicamocha (490-515)	Quetame ()	Ariarí ()		SJ del Guaviare (490-590)	San Isidro ()				[56][57]
515	Early Cambrian		Cambrian explosion										[55][58]
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	[59][60]
600	Neoproterozoic		Cariri Velhos orogeny	Bucaramanga (600-1400)				pre-Guaviare					[56]
800			Snowball Earth										[61]
1000	Mesoproterozoic		Sunsás orogeny			Ariarí (1000)			La Urraca (1030-1100)				[62][63][64][65]
1300			Rondônia-Juruá orogeny			pre-Ariarí	Parguaza (1300-1400)		Garzón (1180-1550)				[66]
1400				pre-Bucaramanga									[67]
1600	Paleoproterozoic						Maimachi (1500-1700)		pre-Garzón				[68]
1800			Tapajós orogeny				Mitú (1800)						[66][68]
1950			Transamazonic orogeny				pre-Mitú						[66]
2200			Columbia
2530	Archean		Carajas-Imataca orogeny										[66]
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]}

Geology of the Eastern Hills

Geology of the Ocetá Páramo

Geology of the Altiplano Cundiboyacense