Tectonic evolution of the Bermejo Basin from broken plate fluxural model (preliminary study)

CARUGATI, GUILLERMO; NOVARA, IVAN; GIMENEZ, MARIO E; INTROCASO, ANTONIO

Mar del Plata

Congreso; Geosur 2010; 2010

OGS -Italia y Instituto Daniel Valencio - UBA

In this study paper, we propose an elastic isostatic flexural model as dominant mechanism in the generation of structures of the Bermejo foreland basin. The study area behaved differently from the Neogene on, it was divided into at least two stages. The first one, from the formation of the Andean foreland basin up to the begining of the Western Sierras Pampeanas lifting. In this stage, the elastic flexure was the predominant mechanism. The second stage, which is the reason for this piece of work, comprises from the reactivation of the megafault of Bermejo-Desaguadero up to now. In this megafault the continuous plate elastic bending mechanism is interrupted and begins to act the elastic bending mechanism on the discontinuous or broken crust. The flexural responses obtained for an elastic thickness crust equivalent to 5 to 7 km, generate a geometry consistent with the current Bermejo basin. These responses are also consistent with the crustal models previously justified from the Bouguer residual anomaly.