Groundwater flow in a closed basin with a saline shallow lake in a volcanic area: Laguna Tuyajto, northern Chilean Altiplano of the Andes.

摘要: Laguna Tuyajto is a small, shallow saline water lake in the Andean Altiplano of northern Chile. In eastern side it fed by springs that discharge groundwater nearby volcanic aquifers. The area arid: rainfall does not exceed 200mm/year rainiest parts. stable isotopic content spring shows recharge originated mainly from winter rain, snow melt, and to lesser extent some short intense sporadic events. Most outflowing recharged volcano. are at higher elevations, rims endorheic basins Pampa Colorada Las Tecas East. presence tritium deep wells indicates recent recharge. Gas emission volcanoes increase sulfate atmospheric deposition this reflected local groundwater. chemical composition concentration waters result meteoric evapo-concentration, water-rock interaction, dissolution old buried evaporitic deposits. Groundwater flow mostly due low permeability ignimbrite layer regional extent, which also hinders brine spreading below around lake. High temperatures near volcano explain high dissolved silica contents δ(18)O shift heavier values found waters. terminal where salts cumulate, halite, but transfer Salar de Aguas Calientes-3 cannot be excluded. hydrogeological behavior constitutes model understand functioning many other similar areas Altiplano.