Contribución a la paleogeografía del Devónico-Carbonífero de la Cordillera Oriental de los Andes Colombianos : una comparación de la mineralogía cuantitativa de las coberteras sedimentarias paleozoicas de los macizos de Quetame y Floresta

Abstract

This work presents new mineralogical and geochemical data of the Precambrian basements and the Paleozoic sedimentary coverts of the Quetame and Floresta massifs in the Eastern Cordillera of the Colombian Andes. The mineralogical and geochemical analyses by X-ray´s diffraction and fluorescence reveal that the sedimentary contributions for the areas of the Quetame (Cundinamarca and Meta) and Floresta (Boyacá) massifs had the same origin during the Paleozoic: the Guyana Shield. The mineralogical differences between the - 6 - sedimentary covers are due to differences in the accumulation environments due to their differential positions with respect to the coastline. Our findings allow us to infer that during the Middle Devonian the area of the Quetame Massif was in a position closer to the continent (Areniscas de Gutiérrez Fm) than the area of the Floresta Massif, which was found in deeper marine sedimentary environments (El Tíbet and Floresta formations). In the early Carboniferous, the positions are reversed with respect to the coastline, the area of the Floresta Massif was closer to the mainland (Cuche Fm) while the area of the Quetame Massif was in a deeper position represented by the Capas Rojas del Guatiquía Fm.