Thick-skinned tectonic style resulting from the inversion of previous structures in the southern Cordillera Oriental (NW Argentine Andes)
N. Carrera, J. A. Muñoz, 2013. "Thick-skinned tectonic style resulting from the inversion of previous structures in the southern Cordillera Oriental (NW Argentine Andes)", Thick-Skin-Dominated Orogens: From Initial Inversion to Full Accretion, M. Nemčok, A. Mora, J. W. Cosgrove
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Structures mapped in the southern Cordillera Oriental of the Andes show an unexpected geometry in an east–west cross-sectional view, with a remarkable predominance of west-directed thrusts. Although some of the Andean structures trend north–south perpendicular to the main east–west direction of Andean shortening, many of them clearly differ from this expected orientation. This peculiar structural style has been largely related to the inversion of the Cretaceous Salta Rift Basin; however, some of these anomalously trending Andean folds and faults do not result from the inversion of Cretaceous faults. This lack of inversion of some Cretaceous structures becomes evident where west-dipping extensional faults rest in the footwall of west-directed thrusts instead of developing east-directed thrusts, as would be expected. Detailed study of several structures and examination of the geometry and facies distribution of several basins highlight not only the role played by the inversion of Cretaceous extensional faults on the geometry of the Andean structures, but also that played by basement anisotropies on the development of both the Cretaceous extensional faults and the Andean contractional structures.
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Thick-Skin-Dominated Orogens: From Initial Inversion to Full Accretion
This volume studies the driving dynamic for thick-skin tectonics. It evaluates the role of various factors that control the development of thick-skin architecture. The studied driving dynamics include individual plate movement rates, overall convergence rates, orogen movement sense with respect to mantle flow and pro-wedge versus retro-wedge location. Numerous internal factors that influence the architecture of thick-skinned dominated orogens have been considered. These include the role of the rheology of the deforming layers, the presence or absence of potential detachment horizons, basement buttresses, crustal thickness variations, inherited strength contrasts and the impact of pre-existing anisotropy in thick-skin orogenic deformation. External factors discussed include the role of both syn-tectonic erosion and deposition in deformation.
The study areas begin with worldwide examples and close with a detailed coverage of the Northern Andes natural laboratory, which is characterized by particularly robust data coverage.