Reactivation, inversion and basement faulting and thrusting in the Sierras Pampeanas of Córdoba (Argentina) during Andean flat-slab deformation
| Autor: | Alina B. Guereschi, Ana Caro Montero, Roberto Donato Martino |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
geography
geography.geographical_feature_category Rift Andean orogeny 010504 meteorology & atmospheric sciences ANDEAN DEFORMATION Inversion (geology) THICK SKINNED STYLE Geology Fault (geology) 010502 geochemistry & geophysics 01 natural sciences Ciencias de la Tierra y relacionadas con el Medio Ambiente Paleontology Craton Mountain chain FAULTING EASTERN SIERRAS PAMPEANAS Meteorología y Ciencias Atmosféricas Foreland basin Seismology CIENCIAS NATURALES Y EXACTAS 0105 earth and related environmental sciences Terrane |
| Popis: | The Sierras Pampeanas of Córdoba are the easternmost uplifted blocks caused by Andean foreland deformation, over 700 km from the Chile trench. This deformation started at c. 340 Ma through basement faults, thrusts and reactivation of normal faults of the Cretaceous rift during the opening of the Atlantic Ocean. Other older faults, major oblique lineaments, were also reactivated. Thermochronological and geothermobarometric data indicate that some topographic relief could have been Palaeozoic-Mesozoic relicts and not only produced by the Andean orogeny. Faults are partially controlled by the early Cambrian S2 metamorphic foliation, coincident with the curved fault traces at map scale. During Pliocene time, two deformation phases post-dating Miocene-Pliocene magmatism are recognized. Shallow seismicity data (c. 25 km depth) indicate that the Sierras de Córdoba accommodate Quaternary displacement. Magnetotelluric studies detect the interface between the Pampia terrane and the Río de la Plata craton. The role of the oblique lineaments in the nucleation and development of the Tertiary faulting has been little considered; they could be correlated with an old pan-Gondwanan trend. During the Cretaceous period these lineaments worked in a transtensive way, producing the uplift of high-grade rocks and segmentation of the mountain chain favouring the diachronous uplift along the ranges. Recently, both the brittle-ductile transition at c. 23 km depth and the crustal thickness have been determined by seismicity analysis. The oblique lineaments displace normally the Mohorovicic discontinuity. Main basement thrusts were probably rooted in the suture between the Pampia terrane and the Río de la Plata craton. Fil: Martino, Roberto Donato. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentina Fil: Guereschi, Alina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentina Fil: Caro Montero, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentina |
| Databáze: | OpenAIRE |
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