Artículos de revistas
Influence of pre-Andean history over Andean foreland deformation: structural styles in the Malargüe fold-and-thrust belt at 35ºS, Andes of Argentina
Fecha
2014-05Registro en:
Mescua, Jose Francisco; Giambiagi, Laura Beatriz; Tassara Oddo, Andres Humberto; Gimenez, Mario Ernesto; Ramos, Victor Alberto; Influence of pre-Andean history over Andean foreland deformation: structural styles in the Malargüe fold-and-thrust belt at 35ºS, Andes of Argentina; Geological Society of America; Geosphere; 10; 3; 5-2014; 585-609
1553-040X
CONICET Digital
CONICET
Autor
Mescua, Jose Francisco
Giambiagi, Laura Beatriz
Tassara Oddo, Andres Humberto
Gimenez, Mario Ernesto
Ramos, Victor Alberto
Resumen
We present the first complete balanced cross-section of the Argentinean Andes at 35ºS. Based on an extensive field survey and limited sub-surface information, we constructed a structural model in which both the tectonic inversion of Mesozoic normal faults and the formation of Cenozoic Andean thrusts play a role in the deformation. We obtained a shortening of 26.2 km, equivalent to 22% of the initial length. This value is lower than previous estimates obtained from partial cross-sections using non-inversion structural models. Comparison of our results with a geophysical model of the crust indicates that: (i) crustal thickness was not constant across the orogen before Andean shortening, but a thick (~45 km) crustal block was interpreted? in the west as a remnant of a Late Paleozoic orogeny, and a thinner sector (~32 km) was located in the east as a result of Mesozoic stretching; and (ii) the structural model presented in this work is more consistent with the regional shortening and crustal thickness trends than models which do not take into account tectonic inversion.