Quaternary Paleoclimatic Record from Tropical South America: Drilling the Salar de Uyuni, Bolivia

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AbstractATM-9809612Baker, PaulDuke UniversityTitle: Quaternary Paleoclimatic Record from Tropical South America: Drilling the Salar de UyuniThis award supports a project to drill the Salar de Uyuni in order to recover a 300-meter long core, representing a history of about 0.5Myr. The core will be analyzed using a multi-proxy approach to reconstruct a climatological (effective moisture and temperature) time series of the Altiplano. Dating will be done by 14C, Ar/Ar, and U/Th methods. Detailed studies of the sedimentology, fluid inclusion petrography, stable isotopic and elemental geochemistry, and paleobiota (diatoms) will form the basis for the climatological reconstruction. The following majors questions will be addressed: (1) What was the nature of late Pleistocene climate variability in tropical South America ? (2) Was tropical South America wet or dry during glacial stages? (3) Are terrestrial tropical climate changes consistent with Milankovitch forcing and are they synchronous with high latitude changes? What climatic mechanisms (e.g. changes in the concentration of atmospheric water vapor) are responsible for these changes? (4) What are the dominant frequencies of suborbital-scale climatic changes in the tropics and are these variations in the terrestrial tropics synchronous with those at higher latitudes? What climatic mechanisms are responsible for these paleoclimatic characteristics?