Hydrochemical measures and salinity studies in Inhanhuns' waters, Ceara State, Brazil

The Inhamuns region is one of the most arid in Ceara Waters exhibit very high salinity. Here we evaluate measurements of chemical parameters (electrical conductivity, EC, and major ions) and δ18 O for waters from wells, springs and surface reservoirs. Results show that springs, with EC of up to nearly 5000 μS/cm, are fed by pluvial water, exchange through dams can be excluded. Electrical conductivity is well correlated with Na+ Mg++ and Cl- for waters of various origins, whereas Ca++ correlates reasonably only for wells. We conclude that aerosol deposition is a major source of salt, Enrichment through evaporation constitutes the most important process for surface water salination. Dissolution of chlorite-silicates is the cause for the magnesian character of underground water. (author)