QUANTIFICATION OF THE WATER BALANCE AND HYDROGEOLOGICAL PROCESSES OF GROUNDWATER-LAKE INTERACTIONS IN THE PAMPA PLAIN, ARGENTINA

BOCANEGRA, E.M.; QUIROZ LONDOÑO, M.; MARTÍNEZ, D.E.; ROMANELLI A.

Environmental Earth Sciences

Springer

Año: 2013 vol. 68 p. 2347 - 2357

1866-6280

This paper gives an account of the assessmentand quantification of the water balance and the hydrogeological processes related to lake groundwater interaction inthe Pampa Plain by using hydrogeochemical, isotopic and flow numerical modeling techniques. La Salada is a permanent shallow lake, with an area of 5.8 km2, located on the SE of Buenos Aires Province. A total of 29 lake water samples and 15 groundwater samples were collected for both hydrochemical analysis and environmental stable isotope determination. Water table depths were measured in wells closed to the lake. Groundwater samples appear grouped on the Local Meteoric Water Line, suggesting a well-mixed system and that rainfall is the main recharge source to the aquifer. Water evaporation process within La Salada is also corroborated by its isotopic composition. The model that best adjusts to La Salada Lake hydrochemical processes includes evaporation from groundwater, calcite precipitation with CO2 release and cationic exchange.