Portal de Periódicos da CAPES

The Sierra de Velasco (northwestern Argentina) an example for polyphase magmatism at the margin of Gondwana

2008; E. Schweizerbart; Volume: 246; Issue: 3 Linguagem: Inglês

10.1127/0077-7749/2007/0246-0325

2363-717X

Alejandro J. Toselli, Hubert Miller, Florencio Gilberto Aceñolaza, Juana N. Rossi, Frank Söllner,

Geological and Tectonic Studies in Latin America

The Sierra de Velasco is formed of large plutons that are related to each other by intrusive contacts and separated by generally aligned deformation zones.The plutons are composed of calc-alkaline, syn-, late-and post-kinematic granitoids of different ages and intrusion levels.They are grouped in three large batholiths: Aimogasta, Bazn and PatquÌa.On the northeastern flank, the metamorphic country rock is represented by micaschists, phyllites and quartzites with hornfels (La Cbila Formation), to the north by tonalitic porphyries that in all cases demonstrate a shallow level of the granitoid intrusions.Shape of the plutons, as well as structural characters and grade of deformation indicate that the intrusive sequences began in Ordovician times and culminated in the Carboniferous, with deformation periods during Silurian and Devonian times.