THE LATE-GLACIAL MORAINE SEQUENCES IN MEXICO - IS THERE EVIDENCE FOR THE YOUNGER DRYAS EVENT

Geomorphologic, paleopedologic, tephrostratigraphic, and palynologic investigations together with radiocarbon dates provide ages for several late Quaternary glacier advances on the volcanoes of central Mexico. On the volcanoes La Malinche, Nevado de Toluca, and Iztaccihuatl, glacier advances have been dated older than 12,000 yr B.P. and between about 10,000 and 8500 yr B.P. The glacial chronostratigraphies from different volcanoes do not indicate a Younger Dryas glacial advance. During the late Quaternary phases with glacier advances can be correlated to changes in Laurentide ice sheet meltwater discharge into the Gulf of Mexico on the one hand and into the North Atlantic Ocean on the other hand. The central Mexican glacial history shows a regional pattern that is different from that of the Rocky Mountains or the South American Andes.