North Andes plate | |
---|---|
Type | Micro |
Movement1 | North-west |
Speed1 | 23mm/year |
Features | Colombia Ecuador Venezuela |
1Relative to the African plate |
The North Andes plate or North Andes block is a small tectonic plate (microplate) located in the northern Andes. It is squeezed between the faster moving South American plate and the Nazca plate to the southwest. Due to the subduction of the Coiba and Malpelo plates, this area is very prone to volcanic and seismic activity, with many historical earthquakes.
The North Andes plate is bound by (clockwise from north):
The Colombian part of the North Andes plate is subdivided into several terranes: [3]
Subduction of the Coiba plate underneath the North Andes plate causes frequent earthquakes in the Bucaramanga Nest, the most seismically active area in the world. The Bucaramanga-Santa Marta Fault stretches along the plate for more than 600 kilometers from north to south. The plate boundary with the South American plate is most tectonically active along a more than 900 kilometer long megaregional fault system; the Eastern Frontal Fault System.
This fault system, extending into Ecuador and Venezuela all along the northern Andes, separates the terranes from the North Andes plate from: [3]
Abbr | Name | Age range | Basins | Complexes | Ranges | Departments | Comments | Notes |
---|---|---|---|---|---|---|---|---|
PRNJ | Río Negro-Juruena Province | Paleoproterozoic | • Llanos • Putumayo • Amazonas | Mitú, Parguaza, Guaviare | Chiribiquete, Mavecure | Arauca, Caquetá, Casanare, Guainía, Guaviare, Meta, Putumayo, Vaupés, Vichada | Part of Amazonian Craton | [14] [15] |
The Chicamocha Canyon is a steep sided canyon carved by the Chicamocha River in Colombia. With a maximum depth of 2,000 metres (6,600 ft), an area of 108,000 hectares and a length of 227 kilometres (141 mi), the canyon is the second-largest worldwide. The canyon is situated in the departments of Boyacá and Santander, stretching from Soatá in the southeast to Girón and Betulia in the northwest.
The Middle Magdalena Valley, Middle Magdalena Basin or Middle Magdalena Valley Basin is an intermontane basin, located in north-central Colombia between the Central and Eastern Ranges of the Andes. The basin, covering an area of 34,000 square kilometres (13,000 sq mi), is situated in the departments of Santander, Boyacá, Cundinamarca and Tolima.
The Cacho Formation (Spanish: Formación Cacho, E1C, Tpc, Tec) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly sandstone formation with thin intercalated beds of shales dates to the Paleogene period; Middle to Late Paleocene epochs, and has a maximum thickness of 400 metres (1,300 ft).
The Honda Group is a geological group of the Upper and Middle Magdalena Basins and the adjacent Central and Eastern Ranges of the Colombian Andes. The group, in older literature also defined as formation, is in its present-day type section in the Tatacoa Desert in the department of Huila subdivided into two main formations; La Victoria and Villavieja.
The Murca Formation is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The predominantly subarkose sandstone with claystones and siltstones formation dates to the Early Cretaceous period; Valanginian epoch and has a maximum thickness of 924 metres (3,031 ft).
The Capotes Formation is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consists of calcareous black shales containing gypsum and ammonites and dates to the Early Cretaceous period; Early Albian epoch and has an approximate thickness at its type section of 550 metres (1,800 ft).
The Bucaramanga–Santa Marta Fault or Bucaramanga–Santa Marta fault system is a major oblique transpressional sinistral strike-slip fault in the departments of Magdalena, Cesar, Norte de Santander and Santander in northern Colombia. The fault system is composed of two main outcropping segments, the Santa Marta and Bucaramanga faults, and an intermediate Algarrobo Fault segment in the subsurface. The system has a total length of 674 kilometres (419 mi) and runs along an average north-northwest to south-southeast strike of 341 ± 23 from the Caribbean coast west of Santa Marta to the northern area of the Eastern Ranges of the Colombian Andes.
The Macanal Formation or Macanal Shale is a fossiliferous geological formation of the Altiplano Cundiboyacense and Tenza Valley in the Eastern Ranges of the Colombian Andes. The predominantly organic shale formation dates to the Early Cretaceous period; Berriasian to Valanginian epochs and has a maximum thickness of 2,935 metres (9,629 ft). The Macanal Formation contains numerous levels of fossiliferous abundances. Bivalves, ammonites and fossil flora have been found in the formation.
The Guavio Formation is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consists of conglomerates, shales and limestones, dates to the Late Jurassic and Early Cretaceous periods; Tithonian to Berriasian epochs and has a maximum thickness of 1,000 metres (3,300 ft).
The Romeral fault system is a megaregional system of major parallel and anastomosing faults in the Central Ranges of the Colombian Andes and the Cauca, Amagá, and Sinú-San Jacinto Basins. The system spans across ten departments of Colombia, from northeast to south Bolívar, Sucre, Córdoba, Antioquia, Caldas, Risaralda, Quindío, Valle del Cauca, Cauca and Nariño. The fault zone extends into Ecuador where it is known as the Peltetec fault system. The in detail described part of the Romeral fault system south of Córdoba has a total length of 697.4 kilometres (433.3 mi) with a cumulative length of 1,787.9 kilometres (1,110.9 mi) and runs along an average north to south strike of 017.6 ± 16, cross-cutting the central-western portion of Colombia.
The Hondita Formation is a fossiliferous geological formation of the Upper Magdalena Valley (VSM) and surrounding Central and Eastern Ranges of the Colombian Andes, extending from Cundinamarca in the north to Huila and easternmost Tolima in the south. The lowermost unit of the Güagüaquí Group, a sequence of sandy limestones and shales, dates to the Late Cretaceous period; Turonian epoch, and has a maximum thickness of 90 metres (300 ft).
The Bogotá Fault is a major inactive slightly dextral oblique thrust fault in the department of Cundinamarca in central Colombia. The fault has a total length of 79.3 kilometres (49.3 mi), while other authors designate a length of 107 kilometres (66 mi), and runs along an average north-northeast to south-southwest strike of 013.5 ± 7 across the Altiplano Cundiboyacense, central part of the Eastern Ranges of the Colombian Andes.
The Oliní Group (Spanish: Grupo Oliní, K3k5o, K2ol, Kso) is a fossiliferous geological group of the VMM, VSM and the eastern flanks of the Central and western flanks of the Eastern Ranges of the Colombian Andes. The regional group stretches from north to south across approximately 700 kilometres (430 mi) and dates to the Late Cretaceous period; Coniacian, Santonian and Campanian epochs, and has a maximum thickness of 287 metres (942 ft). Fossils of Eonatator coellensis have been found in the unit, near Coello, Tolima.
La Guajira Terrane is one of the geological provinces (terranes) of Colombia. The terrane, dating to the Late Cretaceous, is situated on the North Andes Plate and borders the Caribbean, Tahamí and Chibcha Terranes along the Bucaramanga-Santa Marta Fault. The southern boundary is formed by the Oca Fault with the Chibcha Terrane.
The Caribbean Terrane is a geological province (terrane) of Colombia. The terrane, dating to the Late Cretaceous, is situated on the North Andes Plate and borders the La Guajira, Chibcha and underlying Tahamí Terrane along the regional Bucaramanga-Santa Marta Fault. The terrane overlies the Tahamí, Arquía and Quebradagrande Terranes along the Romeral Fault System.
The Chibcha Terrane, named after Chibcha, is the largest of the geological provinces (terranes) of Colombia. The terrane, the oldest explored domains of which date to the Meso- to Neoproterozoic, is situated on the North Andes Plate. The megaregional Romeral Fault System forms the contact of the terrane with the Tahamí Terrane. The contact with the Caribbean and La Guajira Terranes is formed by the regional Bucaramanga-Santa Marta Fault. The northeastern boundary is formed by the regional Oca Fault, bounding the La Guajira Terrane. The terrane is emplaced over the Río Negro-Juruena Province of the Amazonian Craton along the megaregional Eastern Frontal Fault System.
The Tahamí or Tahamí-Panzenú Terrane is one of the geological provinces (terranes) of Colombia. The terrane, dating to the Permo-Triassic, is situated on the North Andes Plate. The contact with the Chibcha, Arquía and Quebradagrande Terranes is formed by the megaregional Romeral Fault System. A tiny terrane is located at the contact with the Quebradagrande Terrane; Anacona Terrane.
The Llanos Basin or Eastern Llanos Basin is a major sedimentary basin of 96,000 square kilometres (37,000 sq mi) in northeastern Colombia. The onshore foreland on Mesozoic rift basin covers the departments of Arauca, Casanare and Meta and parts of eastern Boyacá and Cundinamarca, western Guainía, northern Guaviare and southeasternmost Norte de Santander. The northern boundary is formed by the border with Venezuela, where the basin grades into the Barinas-Apure Basin.
The Girón Formation is an extensive geological formation stretching across 325 kilometres (202 mi) from the north in Teorama, Norte de Santander, across the Mesa de Los Santos and Chicamocha Canyon towards west of Nobsa, Boyacá in the northern part of the Altiplano Cundiboyacense in the south. The formation extends across the northern and central part of the Eastern Ranges of the Colombian Andes.
The Noreán Formation is a geological formation of the Eastern Ranges of the Colombian Andes, the Serranía de San Lucas and as basement underlying the southernmost Lower and northern Middle Magdalena Valleys. The formation consists of volcanic and pyroclastic lavas that range from andesites to rhyolites. Vitric, lithic and crystal tuffs and andesitic dikes and hypabyssal bodies are also present in the formation.
{{citation}}
: CS1 maint: multiple names: authors list (link)