Resumen de La glaciación del límite Ordovícico-Silúrico en el Altiplano de Perú.: evidencias e implicaciones tectónicas

Enrique Díaz Martínez, H. Acosta, R. Rodríguez, V. Carlotto, J. Cardenal

• The Lower Paleozoic stiatigraphic sequen ce cropping out immediately to the north of Ayaviri (Peruvian Altiplano) belongs to the Eastern Cordillera tectonostratigraphic domain, and inc/udes the Sandia, San Gabán and Ananea formations. G/acially-striated and faceted c/asts found within the diamictites of the San Gabán Formation provide the first evidence for the late Ashgill-Llandovery glaciation in the Peruvian Altiplano, an area where this unit was previously considered not to be deposited. The marked difference between the Lower Paleozoic sequen ces of the Altiplano and Eastern Cordillera tectonostratigraphic domains suggests important tectonic shortening along the boundary fault zone.