The Lago Fagnano is located in the central part of the Tierra del Fuego Island; it represents a tectonic basin along the strike of the transforming Magallanes-Fagnano fault which cuts across in a roughly E-W orientation the whole Island. Along the northern lake shoreline, an aeromagnetic anomaly (+75 to 30 nT) of around 35 km 2 indicates the presence of an igneous body. Although the magmatic intrusion, called Kranck Pluton, is poorly exposed, the restricted outcrops display a large lithologic variation (from basic to acid terms) within the alkaline field. The pluton is hosted in the dark schists and sedimentary rocks pertaining to the Lower Cretaceous Beauvoir Fm. which were deformed by the Upper Cretaceous Andean compressive tectonics. Brittle structures related to Magallanes- Fagnano transform fault activity affect both the pluton and its host rocks.
Geology and geophysics of the Kranck pluton (Lago Fagnano, Tierra del Fuego, Argentina)
Lodolo E.;
2008-01-01
Abstract
The Lago Fagnano is located in the central part of the Tierra del Fuego Island; it represents a tectonic basin along the strike of the transforming Magallanes-Fagnano fault which cuts across in a roughly E-W orientation the whole Island. Along the northern lake shoreline, an aeromagnetic anomaly (+75 to 30 nT) of around 35 km 2 indicates the presence of an igneous body. Although the magmatic intrusion, called Kranck Pluton, is poorly exposed, the restricted outcrops display a large lithologic variation (from basic to acid terms) within the alkaline field. The pluton is hosted in the dark schists and sedimentary rocks pertaining to the Lower Cretaceous Beauvoir Fm. which were deformed by the Upper Cretaceous Andean compressive tectonics. Brittle structures related to Magallanes- Fagnano transform fault activity affect both the pluton and its host rocks.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
