IDEAN 23403
INSTITUTO DE ESTUDIOS ANDINOS "DON PABLO GROEBER"
Unidad Ejecutora - UE
artículos
Título:
A geodynamic model linking Cretaceous orogeny, arc migration, foreland dynamic subsidence and marine ingression in southern South America
Autor/es:
ECHAURREN, ANDRÉS; NAVARRETE, CESAR; GIMÉNEZ, MARIO; GIANNI, GUIDO M.; FENNELL, LUCAS; QUEZADA, PAULO; DÁVILA, FEDERICO M.; TOBAL, JONATHAN; FOLGUERA, ANDRÉS
Revista:
EARTH-SCIENCE REVIEWS
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2018 p. 437 - 462
ISSN:
0012-8252
Resumen:
This study synthesizes the tectonomagmatic evolution of the Andes between 35°30?S to 48°Swith the aim to spotlight early contractional phases on Andean orogenic building and toanalyze their potential driving processes. We examine early tectonic stages of the differentfold-thrust belts that compose this Andean segment. Additionally, we analyzed the spatiotemporalmagmatic arc evolution as a proxy of dynamic changes in Andean subduction duringcritical tectonic stages of orogenic construction. This revision proposes a hypothesis relatedthe existence of a continuous large-scale flat subduction setting in Cretaceous times with asimilar size to the present-largest flat-slab setting on earth. This potential process would haveinitiated diachronically in the late Early Cretaceous and achieved full development in LateCretaceous to earliest Paleocene times, constructing a series of fold-thrust belts on the retroarczone from 35°30?S to 48°S. Moreover, we assess major paleogeographic changes that tookplace during flat-slab full development in Maastrichtian-Danian times. At this moment, anenigmatic Atlantic-derived marine flooding covered the Patagonian foreland reaching as far asthe Andean foothills. Based on flexural and dynamic topography analyses, we suggest thatfocused dynamic subsidence at the edge of the flat-slab may explain sudden marine ingressionpreviously linked to continental tilting and orogenic loading during a high sea level globalstage. Finally, flat-subduction destabilization could have triggered massive outpouring ofsynextensional intraplate volcanic rocks in southern South America and the arc retraction inlate Paleogene to early Neogene times.
