Fluvial syntectonic features in Cenozoic Pampean Deposits

BOSSI, G.E.; GEORGIEFF, SERGIO M.; MOYANO, MARCELO S.

Basin Analysis Series

IESGLO

Lugar: Salta; Año: 2009 vol. 1 p. 9 - 58

1852-4796

Stelzner in 1873 named "Pampean Ranges" to this Geological Province (in Ramos 1999) because they looked to be "elevated above the Pampas". They are faulted mountain blocks (called "sierras" by their serrated tops) with a nucleus composed of Precambrian to Early Cambrian aged metamorphic and plutonic rocks with intermediate tectonic valleys or "bolsones". The tilted blocky mountains with a general N-S orientation were elevated by reverse faults. The Pampean Ranges Geological Province is located eastward of the main Andes Cordillera forming a rigid old cristalline basement that extendes from the Province of Salta to the northern limit of the La Pampa Province. We might divide the Pampean Ranges in three sections, with Paleozoic and Mesozoic geological histories that are sometimes  notoriously different: the Northern Pampean Ranges extended from the Salinas Grandes of Córdoba to the SaltaProvince; the Southern Pampean Ranges located mainly in the provinces of Córdoba and San Luis, and the Paganzo Basin located mainly in the La Rioja Province (with minor extensions into the Catamarca and San Luis Provinces). The Salinas Grandes of Córdoba could be considered an old lasting extension of the Chaco - Pampean plains, with a long history of sedimentation, starting in the Devonian (Pre - Gondwana), Carboniferous and Permian perhaps Triassic (the Gondwana time), ending up in the Cenozoic.