Paleozoic deformations in the Eastern Cordillera of the Andes at 23ºS (NW Argentina)

  1. J.L. Alonso 1
  2. R. Seggiaro 2
  3. L. Quintana 1
  4. J. Gallastegui 1
  5. M. Bulnes 1
  6. J. Poblet 1
  7. N. Heredia 3
  8. L.R. Rodríguez Fernández 3
  1. 1 Universidad de Oviedo
    info

    Universidad de Oviedo

    Oviedo, España

    ROR https://ror.org/006gksa02

  2. 2 Universidad Nacional de Salta, Buenos Aires
  3. 3 Instituto Geológico y Minero de España
    info

    Instituto Geológico y Minero de España

    Madrid, España

    ROR https://ror.org/04cadha73

Show affiliations +
Journal:
Geotemas (Madrid)

ISSN: 1576-5172

Year of publication: 2012

Issue Title: VIII Congreso Geológico de España, Oviedo, 17-19 de julio, 2012.

Issue: 13

Pages: 1844-1847

Type: Article

DIALNET GOOGLE SCHOLAR

More publications in: Geotemas (Madrid)

Abstract

The Eastern Cordillera, in NW Argentine, belongs to a fold and thrust belt involving Precambrian, Paleozoic, Mesozoic, Tertiary and Quaternary sediments. The Andean cycle began with the rift-related Cretaceous to Paleogene Salta Group, which unconformably overlies Palaeozoic and Precambrian strata. Structural analysis in several patches of Cretaceous rocks over Paleozoic formations has shown that the unconformity angle ranges from 0º to 90º, because the Cretaceous units truncate previous folds. Although the Cretaceous sequence is thrusted and folded, the estimated thrust displacement for the Cretaceous unconformity is smaller than the one for the Pre-Cretaceous formations. So, if we restore the Andean deformation, previous thrust sheets involve the Paleozoic formations. Moreover, the same thrust may dip in opposite directions along its trace, appearing as a normal fault in one sector and as a reverse fault in another one. That is the consequence of folding (thrust related folds), giving rise to the overturning of previous thrusts in some areas.

Data source: Dialnet