The
Subachoque Formation (
Spanish :
Formación Subachoque , Q
1su ) is a
geological formation of the
Bogotá savanna ,
Altiplano Cundiboyacense ,
Eastern Ranges of the
Colombian Andes . The formation consists mainly of sandy
shales and
lignite with
sandstone beds. The Subachoque Formation dates to the
Quaternary period;
Early to Middle Pleistocene epoch (from approximately 2.5 to 1 Ma), and has a maximum thickness of 150 metres (490 ft). It is the lowermost formation of the
lacustrine and fluvio-glacial sediments of
Lake Humboldt .
Etymology
The formation was first defined and named by Helmens and Van der Hammen in 1995 after Subachoque , Cundinamarca .
Description
Lithologies
The Subachoque Formation consists mainly of sandy shales , some organic , with lignite and sandstone beds.
Stratigraphy and depositional environment
The Subachoque Formation is the lowermost of the lagunal and alluvial sequence of the Bogotá savanna. In parts, it conformably overlies the Tilatá Formation and other parts unconformably the Cretaceous Guadalupe Group and the Paleogene Guaduas , Cacho , Bogotá , and Regadera Formations . The Subachoque Formation is overlain by other Quaternary deposits of Lake Humboldt . The age has been estimated to be Early to Middle Pleistocene based on fission track analysis, with reported ages between 2.5 and 1 Ma. The depositional environment has been interpreted as lacustrine and fluvio-glacial with alluvial fans .
Outcrops
The Subachoque Formation is found at its type locality in the western flank of the synclinal of Subachoque and in the western flank of the synclinal of Guasca . The deposition of the Subachoque Formation postdates the main reverse movement of the Bogotá Fault .
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 volcanismSeismic activity
alluvium
Overburden
1 Pleistocene Pleistocene volcanismAndean orogeny 3Glaciations
Guayabo Soatá Sabana Necesidad Guayabo Gigante Alluvial to fluvial (Guayabo)550 m (1,800 ft)
2.6 Pliocene Pliocene volcanism Andean orogeny 3GABI Subachoque
5.3 Messinian Andean orogeny 3Foreland Marichuela Caimán Honda
13.5 Langhian Regional flooding
León hiatus Caja León Lacustrine (León)400 m (1,300 ft) Seal
16.2 Burdigalian Miocene inundationsAndean orogeny 2
C1 Carbonera C1 Ospina Proximal fluvio-deltaic (C1)
850 m (2,790 ft) Reservoir
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 1Foredeep C5 Carbonera C5 Orito Proximal fluvio-deltaic (C5)
Reservoir
25 C6 Carbonera C6 Distal fluvio-lacustrine (C6)
Seal
28 Early Oligocene C7 C7 Pepino Gualanday Proximal deltaic-marine (C7)
Reservoir
32 Oligo-Eocene
C8 Usme C8 onlap Marine-deltaic (C8)
Seal Source
35 Late Eocene Mirador Mirador Coastal (Mirador)
240 m (790 ft) Reservoir
40 Middle Eocene Regadera hiatus
45
50 Early Eocene Socha Los Cuervos Deltaic (Los Cuervos)
260 m (850 ft) Seal Source
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) Reservoir
65 Maastrichtian KT extinction Catatumbo Guadalupe Monserrate Deltaic-fluvial (Guadalupe)
750 m (2,460 ft) Reservoir
72 Campanian End of rifting Colón-Mito Juan
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) Source
93 Cenomanian Rift 2
100 Albian Une Une Caballos Deltaic (Une)500 m (1,600 ft) Reservoir
113 Aptian Capacho Fómeque Motema Yaví Open marine (Fómeque)
800 m (2,600 ft) Source (Fóm)
125 Barremian High biodiversity Aguardiente Paja Shallow to open marine (Paja)
940 m (3,080 ft) Reservoir
129 Hauterivian Rift 1 Tibú- Las Juntas hiatus Deltaic (Las Juntas)910 m (2,990 ft) Reservoir (LJun)
133 Valanginian Río Negro Cáqueza Macanal Rosablanca Restricted marine (Macanal)
2,935 m (9,629 ft) Source (Mac)
140 Berriasian Girón
145 Tithonian Break-up of Pangea Jordán Arcabuco Buenavista Saldaña Alluvial , fluvial (Buenavista)110 m (360 ft) "Jurassic"
150 Early-Mid Jurassic Passive margin 2 La Quinta Noreán hiatus Coastal tuff (La Quinta)
100 m (330 ft)
201 Late Triassic Mucuchachi Payandé
235 Early Triassic Pangea hiatus "Paleozoic"
250 Permian
300 Late Carboniferous Famatinian orogeny Cerro Neiva ()
340 Early Carboniferous Fossil fish Romer's gap Cuche (355-385) Farallones () Deltaic , estuarine (Cuche)900 m (3,000 ft)
360 Late Devonian Passive margin 1 Río Cachirí (360-419) Ambicá () Alluvial -fluvial -reef (Farallones)2,400 m (7,900 ft)
390 Early Devonian High biodiversity Floresta (387-400) Shallow marine (Floresta)
600 m (2,000 ft)
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 ) Guape () Río Nevado ()
488 Late Cambrian Regional intrusions
Chicamocha (490-515) Quetame () Ariarí () SJ del Guaviare (490-590) San Isidro ()
515 Early Cambrian Cambrian explosion
542 Ediacaran Break-up of Rodinia pre-Quetame post-Parguaza El Barro () Yellow: allochthonous basementChibcha Terrane )Río Negro-Juruena Province )
Basement
600 Neoproterozoic Cariri Velhos orogeny Bucaramanga (600-1400) pre-Guaviare
800 Snowball Earth
1000 Mesoproterozoic Sunsás orogeny Ariarí (1000) La Urraca (1030-1100)
1300 Rondônia-Juruá orogeny pre-Ariarí Parguaza (1300-1400) Garzón (1180-1550)
1400 pre-Bucaramanga
1600 Paleoproterozoic Maimachi (1500-1700) pre-Garzón
1800 Tapajós orogeny Mitú (1800)
1950 Transamazonic orogeny pre-Mitú
2200 Columbia
2530 Archean Carajas-Imataca orogeny
3100 Kenorland
Sources
Legend group important formation fossiliferous formation minor formation (age in Ma) proximal Llanos (Medina)
distal Llanos (Saltarin 1A well)
See also
Geology of the Eastern Hills Geology of the Ocetá Páramo Geology of the Altiplano Cundiboyacense
Notes
^ based on Duarte et al. (2019), García González et al. (2009), and geological report of Villavicencio
^ based on Duarte et al. (2019) and the hydrocarbon potential evaluation performed by the UIS and ANH in 2009
References
^ Montoya & Reyes, 2005, p.69
^ Montoya & Reyes, 2005, p.71
^ Geological Map Bogotá, 1997
^ García González et al., 2009, p.27
^ García González et al., 2009, p.50
^ García González et al., 2009, p.85
^ Barrero et al., 2007, p.60
^ Barrero et al., 2007, p.58
^ Plancha 111, 2001, p.29
^ Plancha 177, 2015, p.39
^ Plancha 111, 2001, p.26
^ Plancha 111, 2001, p.24
^ Plancha 111, 2001, p.23
^ Pulido & Gómez, 2001, p.32
^ Pulido & Gómez, 2001, p.30
^ Pulido & Gómez, 2001, pp.21-26
^ Pulido & Gómez, 2001, p.28
^ Correa Martínez et al., 2019, p.49
^ Plancha 303, 2002, p.27
^ Terraza et al., 2008, p.22
^ Plancha 229, 2015, pp.46-55
^ Plancha 303, 2002, p.26
^ Moreno Sánchez et al., 2009, p.53
^ Mantilla Figueroa et al., 2015, p.43
^ Manosalva Sánchez et al., 2017, p.84
^ Plancha 303, 2002, p.24
^ Mantilla Figueroa et al., 2015, p.42
^ Arango Mejía et al., 2012, p.25
^ Plancha 350, 2011, p.49
^ Pulido & Gómez, 2001, pp.17-21
^ Plancha 111, 2001, p.13
^ Plancha 303, 2002, p.23
^ Plancha 348, 2015, p.38
^ Planchas 367-414, 2003, p.35
^ Toro Toro et al., 2014, p.22
^ Plancha 303, 2002, p.21
^ Bonilla et al., 2016, p.19
^ Gómez Tapias et al., 2015, p.209
^ Bonilla et al., 2016, p.22
^ Duarte et al., 2019
^ García González et al., 2009
^ Pulido & Gómez, 2001
^ García González et al., 2009, p.60
Bibliography
Montoya Arenas, Diana María; Reyes Torres, Germán Alfonso (2005), Geología de la Sabana de Bogotá , INGEOMINAS , pp. 1–104
Maps
Buitrago, José Alberto; Terraza M., Roberto; Etayo, Fernando (1998), Plancha 228 - Santafé de Bogotá Noreste - 1:100,000 INGEOMINAS , p. 1, retrieved 2017-06-06 Various, Authors (1997), Mapa geológico de Santa Fe de Bogotá – Geological Map Bogotá – 1:50,000 (PDF) , INGEOMINAS , p. 1, retrieved 2017-03-16
Further reading
Guerrero Uscátegui, Alberto Lobo (1992), Geología e Hidrogeología de Santafé de Bogotá y su Sabana , Sociedad Colombiana de Ingenieros, pp. 1–20
External links
