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La estructura del frente de deformación de la faja plegada y corrida del Agrio a los 38°20'S, Cuenca Neuquina.

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The Agrio fold and thrust belt contains structures formed during the Andean orogeny that involve the basement and the Mesozoic column of the Neuquén Basin. This belt can be divided into an inner zone, dominated by thick-skinned deformation, and an outer zone characterized by thin-skinned deformation and a subordinate participation of the basement. A structural cross section of the outer zone, in the deformation front of the belt, was constructed at 38°20’S based on field and subsurface data. Five N-S to NNE anticlines with both eastward and westward vergence, were interpreted as fault-related folds detached on the Auquilco Formation (Oxfordian). On the field, these anticlines are cored by the Vaca Muerta and Mulichinco Formations (Tithonian-Valanginian) in the western sector of the section, by the Agrio Formation (Hauterivian-Barremian) in the central zone and by the Neuquén Group (Cenomanian-Campanian) in the eastern end. This differential exhumation is related to the thick-skinned structures at depth, formed by two basement blocks whose structural relief decreases from west to east. The restoration of the cross section allows to calculate a tectonic shortening of 5.8 km (13%). The relative sequence of deformation is interpreted through a kinematic model, where two basement slices associated with east-vergent thrusts elevate the folds formed previously in the overlying sedimentary sequence and generate new thin-skinned structures in the eastern sector of the section.
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... La deformación de piel gruesa en el frente de deformación de la faja plegada y corrida del Agrio recobra importancia hacia el sur, fuera del área de estudio. A los 38ºS (~30 km), se reconoce un levantamiento de ~1.5 km (Zamora Valcarce y Zapata 2015), mientras que a los 38º20'S (~68km) se estimó un levantamiento de ~1.7 km (Irastorza et al. 2019). ...
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