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

CARUGATI, G.; NOVARA I.; A. INTROCASO

MAR DEL PLATA

Congreso; GEOSUR 2010; 2010

In this paper an isostatic flexural elastic model is proposed as the main mechanism in Bermejo foreland basins structures? formation. Two periods can be described since the structures? formation, or at least since the Neogene?s time, in which the behaviour has changed. A first one includes an interval since the beginning of the formation of Andean foreland until the beginning of Western Pampean Ranges uplift. In this period the main mechanism was suggested to be elastic flexure in continuous plate. A second and later period, which is analyzed in this paper, includes the lapse since Desaguadero-Bermejo megafault reactivation until present days. In this period the continuous plate elastic mechanism ends, giving place to a broken plate flexural mechanism due to the Desaguadero-Bermejo megafault. Flexural responses have been obtained by considering a 7km equivalent elastic thickness crust. They have provided sedimentary thickness and shallow basin features consistent with previous models obtained from residual Bouguer anomalies.