Spatial distribution of groundwater salinity at pergamino - Arrecifes zone (Buenos Aires Province, Argentina)

Abstract

The application of irrigation at the NE of Buenos Aires Province, Argentina, demands the knowledge of groundwater features, In particular salinity, in order to avoid unsuccessful drillings and to prevent from deterioration of soils, Some previous large scale studies have shown the presence of salty groundwater at different depths at close sites, and well Information Is scarce. The scope of this work is to determine the depth and thickness of the aquifers of the zone and to obtain the spatial distribution of groundwater salinity. Vertical Electrical Soundings were performed and the continuity of the aquifers was analyzed along four transects Integrating previous results. Geostatistical methodology was used to obtain the spatial variability of electrical resistivity of the Pampeano aquifer, which increases to the east. This analysis was also performed to determine the depth of the fresh-salty water interface which deepens at the left margin of Pergamino river and to the SE direction. A transition zone was found, at SE of the study area, west of Arrecifes city, where the fresh salty water Interface and the water table level deepens abruptly. © 2006 Sociedade Brasileira de Geofísica.