Abstract

BUSTAMANTE, Camilo et al. U-Pb LA-ICP-MS GEOCHRONOLOGY AND REGIONAL CORRELATION OF MIDDLE JURASSIC INTRUSIVE ROCKS FROM THE GARZON MASSIF, UPPER MAGDALENA VALLEY AND CENTRAL CORDILLERA, SOUTHERN COLOMBIA. bol.geol. [online]. 2010, vol.32, n.2, pp. 93-109. ISSN 0120-0283.

New U-Pb zircon geochronology from four granitic units sampled along a southeast-northwest transect between the Garzón Massif and the Serranía de las Minas (Central Cordillera), records a Middle Jurassic magmatic activity with two different spatio-temporal domains at ca. 189 Ma and 180-173 Ma. Reconnaissance data suggest that the four granitoids are characterized by mineralogical and geochemical characteristics akin to a continental magmatic arc setting. The new results suggest that the southern Colombian continental margin includes remnants of tectono-magmatic elements formed by the subduction of the Farallon plate under the South American continental margin. This Middle Jurassic arc magmatism is part of the broader Andean scale arc province, and is significant for understanding the tectonic and paleogeographic scenario that characterized the Mesozoic tectonic evolution of the Northern Andes.

Keywords : U-Pb geochronology; Colombia; Jurassic; Intrusive rocks; Garzón Massif; Central Cordillera.