The Southern Central Andes vertical axis tectonic rotations: relations with the deformation pattern

Abstract

Along the Central Andes a pattern of vertical axis tectonic rotations has been paleomagnetically identified.Such rotations are counterclockwise north of Arica Deflection (~19°S) and clockwise to the south. Different hypothesisand models have been proposed to explain the Central Andean Rotation Pattern (CARP). However, the CARP isa subject of ongoing debate. Recently, the quantity, quality, and geographic distribution of paleomagnetic data haveexpanded greatly. Such expansion has been accompanied by an increase in the knowledge of the deformation periodsin the Andes, allowing a more detailed analysis of the temporal and spatial distribution of the detected rotations. Wecompiled and analyzed the available Cenozoic paleomagnetic data for the region extending between 19° and 27.5°S.The results suggest the possible existence of different rotational domains with distinct characteristics. We propose thatin the Southern Central Andes, a close correlation would exist between the style and the temporal and spatial pattern ofdeformation and the amount of recorded vertical axis rotations. However, in order to further investigate such relationship,new paleomagnetic studies are necessary, particularly in the Eastern Cordillera domain, in Paleogene rocks croppingout in the Altiplano-Puna and in Neogene rocks of the forearc.