The Subachoque Formation (Spanish: Formación Subachoque, Q1su) 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.

Subachoque Formation
Stratigraphic range: Early to Mid Pleistocene
~2.5–1 Ma
TypeGeological formation
UnderliesSabana Formation
OverliesTilatá Formation
Guadalupe Gp.
Guaduas Fm., Cacho Fm., Bogotá Fm., Regadera Fm.
Thicknessup to 150 metres (490 ft)
Lithology
PrimaryShale, lignite
OtherSandstone
Location
Coordinates4°57′17.3″N 74°13′07.5″W / 4.954806°N 74.218750°W / 4.954806; -74.218750
RegionBogotá savanna, Altiplano Cundiboyacense
Eastern Ranges, Andes
Country Colombia
Type section
Named forSubachoque
Named byHelmens & Hammen
LocationSubachoque Synclinal
Year defined1995
Coordinates4°57′17.3″N 74°13′07.5″W / 4.954806°N 74.218750°W / 4.954806; -74.218750
RegionCundinamarca
Country Colombia

Paleogeography of the Pleistocene
by Ron Blakey

Etymology

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The formation was first defined and named by Helmens and Van der Hammen in 1995 after Subachoque, Cundinamarca.[1]

Description

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Lithologies

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The Subachoque Formation consists mainly of sandy shales, some organic, with lignite and sandstone beds.[1]

Stratigraphy and depositional environment

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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.[2] The depositional environment has been interpreted as lacustrine and fluvio-glacial with alluvial fans.[1]

Outcrops

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Type locality of the Subachoque Formation on the northwestern Bogotá savanna

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.[1] The deposition of the Subachoque Formation postdates the main reverse movement of the Bogotá Fault.[3]

Regional correlations

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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
Alluvial to fluvial (Guayabo) 550 m (1,800 ft)
(Guayabo)
[4][5][6][7]
2.6 Pliocene
 
Pliocene volcanism
Andean orogeny 3
GABI
Subachoque
5.3 Messinian Andean orogeny 3
Foreland
Marichuela Caimán Honda [6][8]
13.5 Langhian Regional flooding León hiatus Caja León Lacustrine (León) 400 m (1,300 ft)
(León)
Seal [7][9]
16.2 Burdigalian Miocene inundations
Andean orogeny 2
C1 Carbonera C1 Ospina Proximal fluvio-deltaic (C1) 850 m (2,790 ft)
(Carbonera)
Reservoir [8][7]
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 [5][8]
25 C6 Carbonera C6 Distal fluvio-lacustrine (C6) Seal
28 Early Oligocene C7 C7 Pepino Gualanday Proximal deltaic-marine (C7) Reservoir [5][8][10]
32 Oligo-Eocene C8 Usme C8 onlap Marine-deltaic (C8) Seal
Source
[10]
35 Late Eocene
 
Mirador Mirador Coastal (Mirador) 240 m (790 ft)
(Mirador)
Reservoir [7][11]
40 Middle Eocene Regadera hiatus
45
50 Early Eocene
 
Socha Los Cuervos Deltaic (Los Cuervos) 260 m (850 ft)
(Los Cuervos)
Seal
Source
[7][11]
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 [4][5][8][7][12]
65 Maastrichtian
 
KT extinction Catatumbo Guadalupe Monserrate Deltaic-fluvial (Guadalupe) 750 m (2,460 ft)
(Guadalupe)
Reservoir [4][7]
72 Campanian End of rifting Colón-Mito Juan [7][13]
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 [4][7][14]
93 Cenomanian
 
Rift 2
100 Albian Une Une Caballos Deltaic (Une) 500 m (1,600 ft)
(Une)
Reservoir [8][14]
113 Aptian
 
Capacho Fómeque Motema Yaví Open marine (Fómeque) 800 m (2,600 ft)
(Fómeque)
Source (Fóm) [5][7][15]
125 Barremian High biodiversity Aguardiente Paja Shallow to open marine (Paja) 940 m (3,080 ft)
(Paja)
Reservoir [4]
129 Hauterivian
 
Rift 1 Tibú-
Mercedes
Las Juntas hiatus Deltaic (Las Juntas) 910 m (2,990 ft)
(Las Juntas)
Reservoir (LJun) [4]
133 Valanginian Río Negro Cáqueza
Macanal
Rosablanca
Restricted marine (Macanal) 2,935 m (9,629 ft)
(Macanal)
Source (Mac) [5][16]
140 Berriasian Girón
145 Tithonian Break-up of Pangea Jordán Arcabuco Buenavista
Saldaña Alluvial, fluvial (Buenavista) 110 m (360 ft)
(Buenavista)
"Jurassic" [8][17]
150 Early-Mid Jurassic
 
Passive margin 2 La Quinta
Noreán
hiatus Coastal tuff (La Quinta) 100 m (330 ft)
(La Quinta)
[18]
201 Late Triassic
 
Mucuchachi Payandé [8]
235 Early Triassic
 
Pangea hiatus "Paleozoic"
250 Permian
 
300 Late Carboniferous
 
Famatinian orogeny Cerro Neiva
()
[19]
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)
[16][20][21][22][23]
390 Early Devonian
 
High biodiversity Floresta
(387-400)
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)
Guape
()
Río Nevado
()
[24][25][26]
488 Late Cambrian
 
Regional intrusions Chicamocha
(490-515)
Quetame
()
Ariarí
()
SJ del Guaviare
(490-590)
San Isidro
()
[27][28]
515 Early Cambrian Cambrian explosion [26][29]
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 [30][31]
600 Neoproterozoic Cariri Velhos orogeny Bucaramanga
(600-1400)
pre-Guaviare [27]
800
 
Snowball Earth [32]
1000 Mesoproterozoic
 
Sunsás orogeny Ariarí
(1000)
La Urraca
(1030-1100)
[33][34][35][36]
1300 Rondônia-Juruá orogeny pre-Ariarí Parguaza
(1300-1400)
Garzón
(1180-1550)
[37]
1400
 
pre-Bucaramanga [38]
1600 Paleoproterozoic Maimachi
(1500-1700)
pre-Garzón [39]
1800
 
Tapajós orogeny Mitú
(1800)
[37][39]
1950 Transamazonic orogeny pre-Mitú [37]
2200 Columbia
2530 Archean
 
Carajas-Imataca orogeny [37]
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]


See also

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

Notes

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  1. ^ based on Duarte et al. (2019)[40], García González et al. (2009),[41] and geological report of Villavicencio[42]
  2. ^ based on Duarte et al. (2019)[40] and the hydrocarbon potential evaluation performed by the UIS and ANH in 2009[43]

References

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  1. ^ a b c d Montoya & Reyes, 2005, p.69
  2. ^ Montoya & Reyes, 2005, p.71
  3. ^ Geological Map Bogotá, 1997
  4. ^ a b c d e f García González et al., 2009, p.27
  5. ^ a b c d e f García González et al., 2009, p.50
  6. ^ a b García González et al., 2009, p.85
  7. ^ a b c d e f g h i j Barrero et al., 2007, p.60
  8. ^ a b c d e f g h Barrero et al., 2007, p.58
  9. ^ Plancha 111, 2001, p.29
  10. ^ a b Plancha 177, 2015, p.39
  11. ^ a b Plancha 111, 2001, p.26
  12. ^ Plancha 111, 2001, p.24
  13. ^ Plancha 111, 2001, p.23
  14. ^ a b Pulido & Gómez, 2001, p.32
  15. ^ Pulido & Gómez, 2001, p.30
  16. ^ a b Pulido & Gómez, 2001, pp.21-26
  17. ^ Pulido & Gómez, 2001, p.28
  18. ^ Correa Martínez et al., 2019, p.49
  19. ^ Plancha 303, 2002, p.27
  20. ^ Terraza et al., 2008, p.22
  21. ^ Plancha 229, 2015, pp.46-55
  22. ^ Plancha 303, 2002, p.26
  23. ^ Moreno Sánchez et al., 2009, p.53
  24. ^ Mantilla Figueroa et al., 2015, p.43
  25. ^ Manosalva Sánchez et al., 2017, p.84
  26. ^ a b Plancha 303, 2002, p.24
  27. ^ a b Mantilla Figueroa et al., 2015, p.42
  28. ^ Arango Mejía et al., 2012, p.25
  29. ^ Plancha 350, 2011, p.49
  30. ^ Pulido & Gómez, 2001, pp.17-21
  31. ^ Plancha 111, 2001, p.13
  32. ^ Plancha 303, 2002, p.23
  33. ^ Plancha 348, 2015, p.38
  34. ^ Planchas 367-414, 2003, p.35
  35. ^ Toro Toro et al., 2014, p.22
  36. ^ Plancha 303, 2002, p.21
  37. ^ a b c d Bonilla et al., 2016, p.19
  38. ^ Gómez Tapias et al., 2015, p.209
  39. ^ a b Bonilla et al., 2016, p.22
  40. ^ a b Duarte et al., 2019
  41. ^ García González et al., 2009
  42. ^ Pulido & Gómez, 2001
  43. ^ García González et al., 2009, p.60

Bibliography

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  • Montoya Arenas, Diana María; Reyes Torres, Germán Alfonso (2005), Geología de la Sabana de Bogotá, INGEOMINAS, pp. 1–104

Maps

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Further reading

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  • Guerrero Uscátegui, Alberto Lobo (1992), Geología e Hidrogeología de Santafé de Bogotá y su Sabana, Sociedad Colombiana de Ingenieros, pp. 1–20
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