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A Late Quaternary Diatom Record Of Tropical Climatic History From Lake Titicaca (Peru And Bolivia), Pedro M. Tapia, Sherilyn C. Fritz, Paul A. Baker, Geoffrey A. Seltzer, Robert B. Dunbar

Department of Earth and Atmospheric Sciences: Faculty Publications

A composite high-resolution diatom stratigraphy from three piston cores and one box-core in the deep sub-basin of Lake Titicaca reveals large moisture variations during the past 30 kyr in the Altiplano region. Diatom sequences indicate orbital and millennial-scale variability in water level and salinity. The pelagic freshwater diatom species Cyclotella andina and Cyclotella stelligera dominate Glacial-age sediments, suggesting that the lake was above its present outlet. Generally, wet conditions continued until 11,000 cal yr BP, as indicated by high percentages of freshwater planktonic diatoms. Large pulses of benthic diatom species between about 11,000 and 10,000 cal yr BP suggest brief …