Cuyania
| Geology of the Andes |
|---|
 |
| Orogenies |
| Pampean orogeny |
| Famatinian orogeny |
| Gondwanide orogeny |
| Andean orogeny |
| Fold-thrust belts |
|
Central Andean | Patagonian |
| Batholiths |
| Peruvian Coastal | North Patagonian | South Patagonian |
| Subducted structures |
|
Antarctic Plate | Carnegie Ridge | Chile Rise | Farallon Plate (formerly) | Juan Fernández Ridge | Nazca Plate | Nazca Ridge |
| Faults |
| Andean Volcanic Belt |
|
Northern Zone| Peruvian flat-slab | Central Zone | Pampean flat-slab | Southern Zone | Patagonian Gap | Austral Zone |
| Paleogeographic terminology |
|
Arequipa–Antofalla Craton | Chilenia | Chiloé Block | Cuyania | Iapetus Ocean | Madre de Dios Terrane | Mejillonia | Pampia |
The Precordillera Terrane or Cuyania was an ancient microcontinent or terrane whose history affected many of the older rocks of Cuyo in Argentina. It was separated by oceanic crust from the Chilenia terrane which accreted into it at ~420-390 Ma when Cuyania was already amalgamated with Gondwana.[1] The hypothesized Mejillonia Terrane in the coast of northern Chile is considered by some geologists to be a single block with Cuyania.
The San Rafael Block crops out 200 km to the south of the other exposures of Cuyania and is the southern extension of the terrane.[2]
Dalziel 1997 hypothesised that the Precordillera is derived from Laurentia, the core of North America, which was attached to the western margin of South America during the Precambrian when virtually all continents formed a "proto-Gondwana" supercontinent known as Pannotia. The Precordillera was then part of what Dalziel named the "Texas Plateau", a promontory attached to Laurentia similar to the way the Falkland Plateau is attached to South America today. The Texas Plateau was detached from the Gondwana in a rift around 455 Ma after which it collided with the proto-Andean margin of South America, an event known as the Taconic-Famatinian orogeny, and the Precordillera got left behind at its present location within South America.[3]
References
- Notes
- ↑ Rapalini 2005
- ↑ Cingolani & Heredia 2010
- ↑ Dalziel 1997, Abstract
- Sources
- Cingolani, C.; Heredia, S. (2010). "Field guide on the Ordovician of the Sierra Pintada, San Rafael Block, Mendoza". San Miguel de Tucumán, Argentina: Instituto Superior de Correlación Geológica. Retrieved January 2016.
- Dalziel, I. W. (1997). "Neoproterozoic-Paleozoic geography and tectonics: Review, hypothesis, environmental speculation". Geological Society of America Bulletin 109 (1): 16–42. doi:10.1130/0016-7606(1997)109<0016:ONPGAT>2.3.CO;2.
- Rapalini, A. E. (2005). "The accretionary history of southern South America from the latest Proterozoic to the Late Palaeozoic: some palaeomagnetic constraints". Geological Society, London, Special Publications 246 (1): 305–328. Bibcode:2005GSLSP.246..305R. doi:10.1144/GSL.SP.2005.246.01.12. Retrieved January 2016.
- "The Andes — Tectonic Evolution". Department of Geosciences, University of Arizona. August 2002. Retrieved January 2016.