Hydrochemical and isotopic groundwater investigation in the Oltrepo region (Po Valley, Northern Italy)

A hydrogeologic investigation was conducted using hydrochemistry and isotope techniques in the lowland of the Oltrepò region (Po valley, Northern Italy). Groundwater generally displays a calcium bicarbonate facies. Along major discontinuities, the Po valley brines moves upward and mix with fresh groundwater. Stable isotopes of the water molecule indicate the main aquifer recharge areas, corresponding to the alluvial fans of the major rivers flowing from the Apennine towards the Po river. The observed different deuterium excess in groundwater relates to the origin of precipitation and the location of the river drainage basins. A hydraulic connection, underneath the Po river, between the deep aquifers of the Lomellina and the Oltrepò is also evidenced, implying that deep groundwater is recharged in the pre-alpine area and is several thousand years old

A multidisciplinary study of "Benetutti" thermal waters (Tirso Valley, Sardinia)

We report a multidisciplinary study of "Benetutti" thermal waters based on hydrochemistry, isotopic techniques, structural geology and geophysical surveys. Seven thermal waters and two cold spring waters have been studied. Thermal waters show temperature values ranging between 28 degrees C and 42 degrees C, a medium mineralization and a sodium-chloride chemical hydrofacies. Isotopes of the water molecule allowed verifying that these waters have not been affected by isotopic exchange phenomena with the Sardinian granite complex aquifer. VLF-EM (Very Low Frequency-Electromagnetics) surveys were undertaken for a rapid assessment of the distribution of thermal waters over vast areas. A northeast-southwest trend of high conductivity anomalies was revealed. This trend can be correlated to the occurrence of sub-parallel discontinuities along which thermal waters uprise