The volcanic chain forms a water divide in the Andes, separating the Puna de Atacama from the basins Laguna Miscanti and Laguna Miniques.: A catchment area of for the Laguna Miscanti lies in the Cordón de Puntas Negras. Puntas Negras has been affected by glaciation during the Pleistocene, with moraines reaching up to altitude. Possibly, the entire chain was covered with glaciers, and certainly the southern part where several sets of moraines and glacial trimlines have been identified. Water from Cordón de Puntas Negras is a principal water source for Laguna Miscanti.