This award is for support of Phase II of the Patagonian Lake Drilling Project (PATO), a multi-disciplinary, international collaborative effort to recover and analyze long lacustrine cores for paleoenvironmental and paleoclimate history. Based on the results of Phase I, the investigators plan to concentrate PATO Phase II on Lago Cardiel because it contains the most promising sequences in terms of continuity, chronology, temporal resolution, and paleoclimate sensitivity. PATO Phase II aims to: (1) Develop a 3-dimensional sediment and tectonic basin history based on analysis of the obtained seismic profiles and landscape imagery. Physical properties of the dated cores will be used to validate and calibrate the seismic stratigraphy. (2) Further collect and analyze the modern lake and terrestrial components for climate calibration. Sediment traps will document sediment components, stable isotopes and biological proxies. These are needed to understand the hydrological, geochemical and lake productivity changes. (3) Analyze sediment cores recovered during Phase I, estimated from our combined radiocarbon and ash chronology to date back beyond 18,000 years B.P., for magnetic, sedimentological, and geochemical stratigraphy (including stable isotopes on carbonates and organic matter), along with paleoecological stratigraphies for pollen, charcoal, diatoms, and ostracodes (including stable isotopes and amino acid racemization for chronological assessment).
