Pleistocene glaciations in the northern tropical andes, South America (Venezuela, Colombia and Ecuador)

This article presents an overview of glaciation studies in the northern tropical Andes (Venezuela, Colombia and Ecuador) mostly based on glacial geochronological data. The oldest dated evidences of glaciations are recorded in the Colombian Andes at the Bogotá Plain between 3000-3500 m a.s.l., dated between 1-3 Ma. Maximum extent of former glaciers in the northern Andes seems to have occurred prior to the global Last Glacial Maximum (gLGM). In the Venezuelan-Mérida Andes, former glaciers mostly reached the lowest recorded elevations during MIS 5-MIS 4, whereas in the Colombian Andes, the maximum extents are recorded prior to 38 ka. In the Ecuadorian Andes the most extensive glacial cover probably occurred during MIS 8. In the northern tropical Andes, studied glacier advances are mainly related to MIS 2 period between the final gLGM to the Oldest Dryas (~18 ka-15 ka). Glacier advances during the Younger Dryas (~12.7 ka-11.7 ka) are not extensively evidenced and mainly restricted to elevations higher than ~3500 m a.s.l.