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Las Juntas Formation

Coordinates: 5°00′49″N 73°27′27″W / 5.01361°N 73.45750°W / 5.01361; -73.45750
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Las Juntas Formation
Stratigraphic range: Hauterivian
~132–130 Ma
TypeGeological formation
Unit ofCáqueza Group
Sub-unitsArenisca de Almeida Mb.
Lutitas Intermedias Mb.
Arenisca de El Volador Mb.
UnderliesFómeque Fm., Apón Fm.
OverliesMacanal Formation
Thicknessup to 910 m (2,990 ft)
Lithology
PrimarySandstone
OtherShale
Location
Coordinates5°00′49″N 73°27′27″W / 5.01361°N 73.45750°W / 5.01361; -73.45750
RegionAltiplano Cundiboyacense & Tenza Valley
 Eastern Ranges
  Andes
Country Colombia
Type section
Named forCerro Las Juntas
Named byRodríguez & Ulloa
LocationGuateque
Year defined1979
Coordinates5°00′49″N 73°27′27″W / 5.01361°N 73.45750°W / 5.01361; -73.45750
RegionBoyacá
Country Colombia

The Las Juntas Formation or Las Juntas Sandstone (Spanish: (Formación) Areniscas de Las Juntas, Kiaj, Kialj, K1j) is a geological formation of the Altiplano Cundiboyacense and Tenza Valley, Eastern Ranges of the Colombian Andes. The Las Juntas Formation is found in the departments Cundinamarca, Boyacá and Casanare. The predominantly sandstone formation dates to the Early Cretaceous period; Hauterivian epoch, and has a maximum thickness of 910 metres (2,990 ft).

Etymology

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The formation was defined and named in 1979 by Rodríguez and Ulloa after Cerro Las Juntas, Guateque, Tenza Valley, Boyacá.[1][2]

Description

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Lithologies

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The Las Juntas Formation has a maximum thickness of 910 metres (2,990 ft) and is characterised by a sequence of sandstones with interbedded shales.[1]

Stratigraphy and depositional environment

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The Las Juntas Formation, the uppermost unit of the Cáqueza Group, overlies the Macanal Formation and is overlain by the Fómeque Formation and the Apón Formation in the Sierra Nevada del Cocuy.[3] The formation is subdivided into three members, from old to younger; Arenisca de El Volador, Lutitas Intermedias and Arenisca de Almeida. The age has been estimated to be Hauterivian. The formation has been deposited in a near shore deltaic environment,[1][2] with as provenance areas the Santander High and the Guiana Shield.[4] The formation represents a regressive sequence in the present-day Eastern Ranges, as the Rosablanca Formation in the Middle Magdalena Valley.[5]

Outcrops

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Las Juntas Formation is located in the Altiplano Cundiboyacense
Las Juntas Formation
Type locality of the Las Juntas Formation in the Tenza Valley east of the Altiplano Cundiboyacense

The Las Juntas Formation is apart from its type locality east of Guateque, found in Chingaza National Park,[1] in the El Cochal Synclinal east of the Ocetá Páramo,[6] between Lake Tota and Labranzagrande,[7] other parts of the Tenza Valley such as close to Macanal and Almeida.[8]

The Támara Fault thrusts the Las Juntas Formation southeastward on top of the Tertiary San Fernando and Diablo Formations,[9] and the Chámeza Fault thrusts the older Macanal Formation on top of the Las Juntas Formation around Chámeza, Casanare.[10]

Regional correlations

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Cretaceous stratigraphy of the central Colombian Eastern Ranges
Age Paleomap VMM Guaduas-Vélez W Emerald Belt Villeta anticlinal Chiquinquirá-
Arcabuco
Tunja-
Duitama
Altiplano Cundiboyacense El Cocuy
Maastrichtian Umir Córdoba Seca eroded Guaduas Colón-Mito Juan
Umir Guadalupe
Campanian Córdoba
Oliní
Santonian La Luna Cimarrona - La Tabla La Luna
Coniacian Oliní Villeta Conejo Chipaque
Güagüaquí Loma Gorda undefined La Frontera
Turonian Hondita La Frontera Otanche
Cenomanian Simití hiatus La Corona Simijaca Capacho
Pacho Fm. Hiló - Pacho Churuvita Une Aguardiente
Albian Hiló Chiquinquirá Tibasosa Une
Tablazo Tablazo Capotes - La Palma - Simití Simití Tibú-Mercedes
Aptian Capotes Socotá - El Peñón Paja Fómeque
Paja Paja El Peñón Trincheras Río Negro
La Naveta
Barremian
Hauterivian Muzo Cáqueza Las Juntas
Rosablanca Ritoque
Valanginian Ritoque Furatena Útica - Murca Rosablanca hiatus Macanal
Rosablanca
Berriasian Cumbre Cumbre Los Medios Guavio
Tambor Arcabuco Cumbre
Sources


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)
[11][12][13][14]
2.6 Pliocene
Pliocene volcanism
Andean orogeny 3
GABI
Subachoque
5.3 Messinian Andean orogeny 3
Foreland
Marichuela Caimán Honda [13][15]
13.5 Langhian Regional flooding León hiatus Caja León Lacustrine (León) 400 m (1,300 ft)
(León)
Seal [14][16]
16.2 Burdigalian Miocene inundations
Andean orogeny 2
C1 Carbonera C1 Ospina Proximal fluvio-deltaic (C1) 850 m (2,790 ft)
(Carbonera)
Reservoir [15][14]
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 [12][15]
25 C6 Carbonera C6 Distal fluvio-lacustrine (C6) Seal
28 Early Oligocene C7 C7 Pepino Gualanday Proximal deltaic-marine (C7) Reservoir [12][15][17]
32 Oligo-Eocene C8 Usme C8 onlap Marine-deltaic (C8) Seal
Source
[17]
35 Late Eocene
Mirador Mirador Coastal (Mirador) 240 m (790 ft)
(Mirador)
Reservoir [14][18]
40 Middle Eocene Regadera hiatus
45
50 Early Eocene
Socha Los Cuervos Deltaic (Los Cuervos) 260 m (850 ft)
(Los Cuervos)
Seal
Source
[14][18]
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 [11][12][15][14][19]
65 Maastrichtian
KT extinction Catatumbo Guadalupe Monserrate Deltaic-fluvial (Guadalupe) 750 m (2,460 ft)
(Guadalupe)
Reservoir [11][14]
72 Campanian End of rifting Colón-Mito Juan [14][20]
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 [11][14][21]
93 Cenomanian
Rift 2
100 Albian Une Une Caballos Deltaic (Une) 500 m (1,600 ft)
(Une)
Reservoir [15][21]
113 Aptian
Capacho Fómeque Motema Yaví Open marine (Fómeque) 800 m (2,600 ft)
(Fómeque)
Source (Fóm) [12][14][22]
125 Barremian High biodiversity Aguardiente Paja Shallow to open marine (Paja) 940 m (3,080 ft)
(Paja)
Reservoir [11]
129 Hauterivian
Rift 1 Tibú-
Mercedes
Las Juntas hiatus Deltaic (Las Juntas) 910 m (2,990 ft)
(Las Juntas)
Reservoir (LJun) [11]
133 Valanginian Río Negro Cáqueza
Macanal
Rosablanca
Restricted marine (Macanal) 2,935 m (9,629 ft)
(Macanal)
Source (Mac) [12][23]
140 Berriasian Girón
145 Tithonian Break-up of Pangea Jordán Arcabuco Buenavista
Saldaña Alluvial, fluvial (Buenavista) 110 m (360 ft)
(Buenavista)
"Jurassic" [15][24]
150 Early-Mid Jurassic
Passive margin 2 La Quinta
Noreán
hiatus Coastal tuff (La Quinta) 100 m (330 ft)
(La Quinta)
[25]
201 Late Triassic
Mucuchachi Payandé [15]
235 Early Triassic
Pangea hiatus "Paleozoic"
250 Permian
300 Late Carboniferous
Famatinian orogeny Cerro Neiva
()
[26]
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)
[23][27][28][29][30]
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
()
[31][32][33]
488 Late Cambrian
Regional intrusions Chicamocha
(490-515)
Quetame
()
Ariarí
()
SJ del Guaviare
(490-590)
San Isidro
()
[34][35]
515 Early Cambrian Cambrian explosion [33][36]
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 [37][38]
600 Neoproterozoic Cariri Velhos orogeny Bucaramanga
(600-1400)
pre-Guaviare [34]
800
Snowball Earth [39]
1000 Mesoproterozoic
Sunsás orogeny Ariarí
(1000)
La Urraca
(1030-1100)
[40][41][42][43]
1300 Rondônia-Juruá orogeny pre-Ariarí Parguaza
(1300-1400)
Garzón
(1180-1550)
[44]
1400
pre-Bucaramanga [45]
1600 Paleoproterozoic Maimachi
(1500-1700)
pre-Garzón [46]
1800
Tapajós orogeny Mitú
(1800)
[44][46]
1950 Transamazonic orogeny pre-Mitú [44]
2200 Columbia
2530 Archean
Carajas-Imataca orogeny [44]
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)[47], García González et al. (2009),[48] and geological report of Villavicencio[49]
  2. ^ based on Duarte et al. (2019)[47] and the hydrocarbon potential evaluation performed by the UIS and ANH in 2009[50]

References

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  1. ^ a b c d Acosta & Ulloa, 2002, p.52
  2. ^ a b Rodríguez & Solano, 2000, p.47
  3. ^ Villamil, 2012, p.168
  4. ^ Villamil, 2012, p.165
  5. ^ Villamil, 2012, p.166
  6. ^ Plancha 172, 1998
  7. ^ Plancha 192, 1998
  8. ^ Plancha 210, 2010
  9. ^ Plancha 193, 1992
  10. ^ Plancha 211, 2009
  11. ^ a b c d e f García González et al., 2009, p.27
  12. ^ a b c d e f García González et al., 2009, p.50
  13. ^ a b García González et al., 2009, p.85
  14. ^ a b c d e f g h i j Barrero et al., 2007, p.60
  15. ^ a b c d e f g h Barrero et al., 2007, p.58
  16. ^ Plancha 111, 2001, p.29
  17. ^ a b Plancha 177, 2015, p.39
  18. ^ a b Plancha 111, 2001, p.26
  19. ^ Plancha 111, 2001, p.24
  20. ^ Plancha 111, 2001, p.23
  21. ^ a b Pulido & Gómez, 2001, p.32
  22. ^ Pulido & Gómez, 2001, p.30
  23. ^ a b Pulido & Gómez, 2001, pp.21-26
  24. ^ Pulido & Gómez, 2001, p.28
  25. ^ Correa Martínez et al., 2019, p.49
  26. ^ Plancha 303, 2002, p.27
  27. ^ Terraza et al., 2008, p.22
  28. ^ Plancha 229, 2015, pp.46-55
  29. ^ Plancha 303, 2002, p.26
  30. ^ Moreno Sánchez et al., 2009, p.53
  31. ^ Mantilla Figueroa et al., 2015, p.43
  32. ^ Manosalva Sánchez et al., 2017, p.84
  33. ^ a b Plancha 303, 2002, p.24
  34. ^ a b Mantilla Figueroa et al., 2015, p.42
  35. ^ Arango Mejía et al., 2012, p.25
  36. ^ Plancha 350, 2011, p.49
  37. ^ Pulido & Gómez, 2001, pp.17-21
  38. ^ Plancha 111, 2001, p.13
  39. ^ Plancha 303, 2002, p.23
  40. ^ Plancha 348, 2015, p.38
  41. ^ Planchas 367-414, 2003, p.35
  42. ^ Toro Toro et al., 2014, p.22
  43. ^ Plancha 303, 2002, p.21
  44. ^ a b c d Bonilla et al., 2016, p.19
  45. ^ Gómez Tapias et al., 2015, p.209
  46. ^ a b Bonilla et al., 2016, p.22
  47. ^ a b Duarte et al., 2019
  48. ^ García González et al., 2009
  49. ^ Pulido & Gómez, 2001
  50. ^ García González et al., 2009, p.60

Bibliography

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  • Acosta Garay, Jorge E.; Ulloa Melo, Carlos E. (2002), Mapa Geológico del Departamento de Cundinamarca - 1:250,000 - Memoria explicativa, INGEOMINAS, pp. 1–108, retrieved 2017-04-26
  • Rodríguez Parra, Antonio José; Solano Silva, Orlando (2000), Mapa Geológico del Departamento de Boyacá - 1:250,000 - Memoria explicativa, INGEOMINAS, pp. 1–120
  • Villamil, Tomas (2012), Chronology Relative Sea Level History and a New Sequence Stratigraphic Model for Basinal Cretaceous Facies of Colombia, Society for Sedimentary Geology (SEPM), pp. 161–216

Maps

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