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 to the east and the Nazca plate to the west. Due to the subduction of the Coiba and Malpelo plates, this area is very prone to volcanic and seismic activity, with many historical earthquakes.

Boundaries The North Andes plate is bound by (clockwise from north):

Caribbean plate South American plate Malpelo plate – considered a part of the Nazca plate before 2017Zhang et al., 2017 Coiba plate – considered a part of the Nazca plate before 2016Chiarabba et al., 2016, p.22 Panama plate

Terranes

The Colombian part of the North Andes plate is subdivided into several terranes:Gómez Tapias et al., 2015, p.209

+Terranes belonging to the Colombian part of the North Andes plate Abbr Name Age range Paleomap Basins Complexes Ranges Departments Comments Notes CHT Chibcha Mesoproterozoic • Catatumbo• Cesar-Ranchería• Eastern Cordillera • VMM• VSM Ariarí, Garzón, Floresta, Quetame, Santander Central, Eastern, Perijá, SNSM, San Lucas, La Macarena Antioquia, Arauca, Bogotá, Bolívar, Boyacá, Caquetá, Casanare, Cesar, Cundinamarca, Huila, Magdalena, Meta, Putumayo, Norte de Santander, Santander, Tolima Largest terrane, named after Chibcha Manosalva Sánchez et al., 2017, p.84Mantilla Figueroa et al., 2015, p.42Toro Toro et al., 2014, p.22 Neoproterozoic TA Devonian none Anacona Central Antioquia Tiny terrane Carboniferous TT Tahamí Permian • Amagá• Cocinetas• VIM Antioquia Central, Macuira, SNSM Antioquia, Bolívar, Caldas, Cauca, La Guajira, Magdalena, Nariño, Risaralda, Sucre, Valle del Cauca Most extensive terrane Triassic TAR Arquía Early Cretaceous none Arquía Central Antioquia, Caldas, Cauca, Nariño, Quindío, Risaralda, Valle del Cauca Thinly banded terrane Plancha 364Plancha 365Plancha 387 TQ Quebradagrande none Quebradagrande Central Antioquia, Caldas, Cauca, Nariño, Quindío, Risaralda, Valle del Cauca Thinly banded terrane Plancha 410Plancha 411Plancha 429Plancha 430 TC Caribe Late Cretaceous • Cauca-Patía• Chocó• Sinú-San Jacinto• Tumaco• Urabá Santa Cecilia-La Equis Central, Western, Darién, Baudó, Montes de María Antioquia, Atlántico, Caldas, Cauca, Chocó, Córdoba, Nariño, Quindío, Risaralda, Sucre, Valle del Cauca El Totumo TLG La Guajira • La Guajira Etpana, Macuira Macuira, SNSM La Guajira, Magdalena Tayrona, Cabo de la Vela

Tectonics 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:

+South American plate features bordering the Chibcha terrane of the North Andes plate 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 Bonilla et al., 2016, p.19Arango Mejía et al., 2012, p.25 The accreted terranes of the North Andes plate represent a complex geologic history. There have been two instances of intra-oceanic arcs colliding with the continent. The first of these events, which took place ~90–65 Ma, involved the subduction of an intra-oceanic arc beneath the South American/North Andes plate. This subduction led to margin-parallel strike-slip motion and shortening across the entire region. The second major collision occurred approximately 12 Ma, during the Miocene. This event involved closing a ~1200-km-wide middle-Eocene seaway and docking the Panama arc with South America. This second collision event also accelerated strike-slip faulting along the North Andes margin. Reconstruction studies of the area illustrate the complex dynamics of the tectonically active North Andes plate margin.

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