Further evidences of Quaternary activity of Maradona Faulting (Precordillera Central), Argentina

MOREIRAS S.M., BANCHIG A.L.

Niza, Francia

Simposio; 7th International Symposium on Andean Geodynamics.; 2008

The Maradona faulting is located in the Pampa of Maradona (San Juan province), an NS elongated valley that runs parallel to the Eastern Precordillera and the Central Precordillera (31º 46´ LS - 68º 51´) (Figure 1) continuing towards the south as the Pampa of Bachongo. This faulting, with a total extension of 32 km, was initially identified by photo-interpretation and was considered as a Lower-Middle Pleistocene age fault (Bastías et al., 1984). Further research deduced that this faulting is an expression of the “Matagusanos-Maradona-Acequión” tectonic belt (Perucca, 1990; Perucca et al., 1990) located between the Eastern Precordillera and the Central Precordillera. Both, geological provinces has a completely different structural behaviour. Whereas, the former is characterised by a skinned fold - thrust belt with occidental vergence where  mainly Cambric-Ordovician carbonatic rocks outcrop, the latter corresponds to overthrustings with eastern vergence and its outcroppings are Palaeozoic rocks of talus or outer marine platform. Even through, the Maradona faulting is reported as active during Quaternary (Amos, 1981) detailed geomorphological studies have not been carried out in this area. Hence, this research is focussed to amend this lacking analysing preserved geomorphological expressions of this faulting that may be engaged to evaluate the regional seismic hazard.