Limnogeology of Chungara Lagoon and climatic change during the Upper Holocene in the northern highlands of Chile

We reconstruct the Late Holocene sedimentary history of Laguna Chungara (69 degrees 30' W, 18 degrees 10'S, 4520 m.a.s.l., northern Chilean Altiplano) based on high resolution seismic profiling and sedimentologic analyses of cores. Two sedimentary facies associations have been defined and interpreted: i) macrophyte-dominant littoral, composed of black muds with macrophyte remains and peaty muds, and ii) Characeae-dominant lacustrine self, composed of gray muds and sands with abundant Characeae remains. The two facies associations define three cycles caused by oscillations in the lake level from shallower (macrophyte) to deeper (Characeae) conditions. Changes in the hydrology of Laguna Chungara reflect variations in the effective moisture (precipitation - evaporation) in the Altiplano during the Late Holocene.