The impact of inherited crustal features on the evolution of the Southern Central Andes: insights from numerical modeling

BARRIONUEVO, M.; LIU, SIBIAO; MESCUA, J.; YAGUPSKY, D. L.; QUINTEROS, J.; GIAMBIAGI, L.; RODRIGUEZ PICEDA, C.; STRECKER, MANFRED R.

Congreso; XXI CONGRESO GEOLÓGICO ARGENTINO; 2022

To assess the control of the upper-plate confi guration on deformation patterns, we develop geodynamicalmodels representative of two E-W-transects (33º40´S and 36ºS), which are based on geologicaland geophysical information of the area. Our numerical models demonstrate that the composition ofthe lower crust is an important factor controlling the crustal deformation mode. Particularly, in contrastto the decoupled or simple-shear scenario with dominant lower crustal mafi c lithology (south of35ºS; Fig. 1F), a more felsic composition of the lower crust results in pure-shear deformation (northof 35ºS; Fig. 1C).