Huincul Fault
vitrinite reflectance
. Huincul basement high is shown in grey.The Huincul Fault or Huincul Fault Zone (Spanish: Falla de Huincul, Zona de falla Huincul) is an east-to-west-oriented, continental-scale fault that extends from the Neuquén Basin eastwards into the Argentine Shelf.[1] To the west, it has been proposed to extend across the Andes to the Chilean Coast Range.[2]
In the Neuquén Basin, the fault exhibits a slightly curved path, being convex to the north.[3] It is a major geological discontinuity and it truncates the north-to-south-oriented Pampean orogen, among other structures. Because of this, it has been proposed to represent the northern geological limit of Patagonia.[1]
Origin and development
The fault develops on the
Strike-slip movement along the fault began in the Toarcian.[4] The main stress vector (i.e. direction of compression) was originally northwest-oriented but shifted over time to the north-northwest. In the Late Miocene, the last phase of deformation began with east–west compression followed by tectonic extension in Pliocene times.[2]
The different stages of deformation were a consequence of the successive
plates beneath the plates of Gondwana and then South America.[2]
Geological structures
A
inverted half-grabens.[5] East of city of Neuquén, the fault roughly follows the path of the upper course of Río Negro. In this region, a series of basement highs and small pull-apart basins has formed along the fault, reflecting a clockwise movement.[3]
References
- ^ a b Ramos, V.A.; Riccardi, A.C.; Rolleri, E.O. (2004). "Límites naturales del norte de la Patagonia". Revista de la Asociación Geológica Argentina (in Spanish). 59 (4).
- ^ a b c d e Mosqueira, Alfonso; Silvestro, José; Ramos, Víctor A.; Alarcón, Martín; Zubiri, Martín (2011). "La estructura de la dorsal de Huincul". Relatorio del XVIII Congreso Geológico Argentino, Neuquén, 2011 (in Spanish). pp. 385–397.
- ^ a b Kostadinoff, José; Gregori, Daniel A.; Raniolo, Daniel A. (2005). "Configuración geofísica-geológica del sector norte de la provincia de Río Negro" (PDF). Revista de la Asociación Geológica Argentina (in Spanish). 60 (2): 368–376. Retrieved May 14, 2017.
- ^ a b c d Mosquera, Alfonso; Ramos, Víctor A. (2006). "Intraplate Deformation in the Neuquén Embayment". Geological Society of America Special Papers. 407: 97–123.
- ^ a b c d e Pángaro, Francisco; Pereira, Diego Martín; Micucci, Eduardo (2009). "El sinrift de la dorsal de Huincul, Cuenca Neuquina: evolución y control sobre la estratigrafía y estructura del área". Revista de la Asociación Geológica Argentina (in Spanish). 65 (2).
Major South American geological features | ||
|---|---|---|
| Tectonic plates |  | |
| Cratons and shields | ||
| Structures undergoing subduction | ||
| Faults and shear zones | ||
| Rifts and grabens | ||
| Sedimentary basins | ||
| Orogenies | ||
| Metallogenetic provinces | ||
Volcanic provinces |
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| Hotspots | ||