Lacustrine systems, Isotope fractionation, Climate proxies, Water temperature, Stable isotopes, 18O/16O ratios, O ratios, CARBON, SEDIMENTS, WATER RESOURCES, PALEOCLIMATE, ARGENTINA, ENGINEERING, CIVIL, GEOSCIENCES, MULTIDISCIPLINARY, INDICATORS, DELTA-O-18, SOUTHERN PATAGONIA, O-18/O-16 ratios, STABLE OXYGEN, CELLULOSE, CLIMATE