evolution in a limestone terrain at Zagros region, Iran. The study area includes a deep
confined aquifer, overlaid by an unconfined aquifer. The method involves the use of
principal component analysis (PCA) to assess and evaluate the hydrochemical evolution
based on chemical and isotope variables of 12 piezometers drilled in both the unconfined
and confined aquifers. First PCA on all variables shows that water–rock interaction under …