Abstract:
Cetina et al. (2019) presented new geochronological, geochemical and isotopic data obtained from volcanic and sub-volcanic rocks exposed in the northern segment of the Western Cordillera of Colombia, which are interpreted as related to a Cretaceous island arc-plateau system. These data are used to come up with a paleogeographic model for the circum-Caribbean realm that may account for the presence of old (Paleozoic - Proterozoic) xenocrystic zircons in the analyzed units. Nevertheless, the authors ignored previously published geological, geochemical, geochronological, thermochronological and provenance constraints from Cretaceous rocks of northwestern Colombia, which refuse the plausibility of their proposed models. Particularly, the occurrence of Cretaceous subduction-related metamorphism, magmatism and construction of marginal sedimentary basins, documented by several published papers in the last decade, renders the paleogeographic reconstructions of Cetina et al. (2019) to be unlikely. We demonstrate that when considering the ignored geological evidences, alternative explanations for the origin of pre-Mesozoic xenocrystic zircons are required.
