Va. Ramos et al., CENOZOIC TECTONICS OF THE HIGH ANDES OF WEST-CENTRAL ARGENTINA (30-36-DEGREES-S LATITUDE), Tectonophysics, 259(1-3), 1996, pp. 185-200
The structure of the Central Andes shows three distinctive segments ch
aracterized by different geometries. These geometries are superimposed
on the present large-scale plate tectonic setting characterized by di
stinct subduction segments. The northern La Ramada segment is a thick-
skinned fold and thrust belt formed by tectonic inversion of a Late Tr
iassic rift. The central Aconcagua segment consists of a thin-skinned
fold and thrust belt while the southern Malargue segment like the firs
t one is a thick-skinned fold and thrust belt developed by tectonic in
version of a Late Triassic-Early Jurassic rift system during late Ceno
zoic times. The amount of shortening gradually decreases from north to
south, as indicated by the crustal roots of the Central Andes. The di
fferent geometries along the Principal Cordillera controlled the abrup
t changes in the shortening among segments. The structure of Precordil
lera and Sierras Pampeanas has also been considered in order to accoun
t for the total shortening. In the La Ramada segment the main shorteni
ng occurred in the Precordillera; in the Aconcagua segment in the Prin
cipal Cordillera while in the Malargue segment the shortening is widel
y distributed in a broader Principal Cordillera, because south of the
flat-slab subduction segment the Precordillera and Sierras Pampeanas a
re missing.