Basin fragmentation controlled by tectonic inversion and basement uplift in Sierras Pampeanas and Santa Bárbara System, northwest Argentina

Abstract

The study area is located within the Central Andes, a complex region composed of different structural styles. The region is characterized by highly elevated basement cored ranges, which abruptly break the foreland plain. These ranges were uplifted mainly by deep detached high-angle faults or by the inversion of former extensional faults of the Cretaceous rift. Palaeozoic orogenies generated crustal scale discontinuities in the basement, some of them reactivated during the Andean orogeny. Sedimentary sequences and layers architecture in the basins bordering ranges recorded the tectonic evolution of the region. Basement, syn–rift, post-rift and three foreland stages were interpreted in the seismic sections according to the arrangement of the horizons and the main outcropping geological units in bordering ranges. Based on seismic data sets and field data, here we document a particular style of activation of basement faults. Thick-skinned structures that are not always related to the tectonic inversion but to the reactivation of older basement anisotropies represent a paradox since they were not active during the rifting stage. A flat slab subduction and a subsequent angle recovery conditioned the structural evolution of the area.

Thick-skin-dominated orogens; from initial inversion to full accretion: an introduction

“…8a-d). Field-based studies determining the role of pre-existing anisotropy in thick-skin orogenic deformation are presented in papers by Baby et al (2013), , Iaffa et al (2013) and Kober et al (2013), while the role of the inherited strength contrasts is studied by Morretti et al (2013). The effect of the existence v. non-existence of potential detachment horizons on a large scale is discussed by Carola et al (2013), and on a smaller scale is discussed by Nemčok et al (2013).…”

“…The effect of the existence v. non-existence of potential detachment horizons on a large scale is discussed by Carola et al (2013), and on a smaller scale is discussed by Nemčok et al (2013). The role of buttressing effects of basement blocks is documented by Carrera & Muñoz (2013) and Iaffa et al (2013). A detailed description of the structural architecture development from initial inversion to full accretion stages is given by Teixell & Babault (2013).…”

“…7, Table 1). This volume attempts to follow this strategy by examining the factors involved in the energy balance behind inversion and the potential subsequent full accretion from thick-skin regions worldwide (Baby et al 2013;Carola et al 2013;Carrera & Muñoz 2013;Iaffa et al 2013;Kober et al 2013;Moretti et al 2013;Nemčok et al 2013;Teixell & Babault 2013;Fig. 8a-d) and by considering the systematic data collection from the Northern Andes, an example of the forceful retro-wedge scenario (Bayona et al 2013;Caballero et al 2013a, b;Hermeston & Nemčok 2013;Jimenez et al 2013;Mora et al 2013;Moreno et al 2013;Silva et al 2013;Teixell & Babault 2013;Tesón et al 2013;Fig.…”

“…Some thrust belts, such as the Andes, change style along-strike (Allmendinger et al 1997;Baby et al 2013; Carrera & Muñoz 2013;Iaffa et al 2013;Moretti et al 2013). Other thrust belts, such as the US Cordillera -Rocky Mountains, exhibit thin-skin structural styles in their interior and thick-skin style in their exterior (Hamilton 1988).…”

“…They have evolved from either passive margins or intra-cratonic rift systems. The most typical examples of the former (initial passive margin setting) are various Andean thick-skin provinces, the Tienshan and the Western Alps (Schmid et al 1996(Schmid et al , 1997Escher & Beaumont 1997;Baby et al 2013;Carrera & Muñoz 2013;Iaffa et al 2013;Kober et al 2013;Tesón et al 2013). The most typical examples of the latter (initial intra-cratonic setting) include the High Atlas, Middle Atlas, central and eastern Pyrenees and the Palmyrides (Carola et al 2013;Teixell & Babault 2013).…”