sentences:  Glaciers of the ice sheet also reworked previously deposited layers.Some 10,300 years ago Choshuenco produced the Neltume Pumice during a plinian eruption.The earliest historical accounts of eruptions from the Mocho-Choshuenco complex may be those in Alonso de Ovalle's map "Tabula Geographica Regni Chile" from 1646.