17 Geomorphology/Quaternary Geology (Posters)

Sunday, 22 March 2009
1:00 PM - 5:00 PM

LATE QUATERNARY GLACIAL CHRONOLOGY NEVADO ILLIMANI, CORDILLERA REAL, BOLIVIA: IMPLICATIONS FOR PALEOCLIMATIC RECONSTRUCTIONS ACROSS THE ANDES

Paper number: 17-8
Program: Technical Sessions
Time: 1:00 PM – 5:00 PM

Authors

Abstract

New 10Be surface exposure ages from moraines on Nevado Illimani, Cordillera Real, Bolivia suggest that glaciers retreated from moraines during the periods 15.0 ka -13.0 ka; 10.5 ka - 8.5 ka, and 3.0 ka - 1.5 ka. Late Glacial moraines at Illimani are associated with an ELA depression of ~400 m, which is consistent with other local reconstructions of Late Glacial ELAs in the Eastern Cordillera of the central Andes. Reconstructed ELA gradients across the Andes based on dated Late Glacial moraines suggest a change in slope of the regional ELA that is consistent with increased precipitation from the west.