RT info:eu-repo/semantics/article T1 Determining groundwater quality based on volcanic terrain: a case study from the Island of Tenerife, Spain A1 Miguel García, Eduardo de A1 Gómez González, José Francisco A1 Cruz, J. L. K1 Groundwater K1 Volcanic terrain K1 Lithology AB This research analyses the water of 258 significant tunnels throughout the Island of Tenerife used to obtaingroundwater and establishes a clear relationship between the qualities of the water and the volcanic lithologiesof the island of Tenerife.Each water sample from each tunnel was taken to an approved laboratory for analysis, where the values ofCa2+, Mg+, Na2+, K+, HCO3− , CO32− , Cl− , SO42− , NO3− , H2PO4− , SiO2 and F, as well as water quality parameters,namely electrical conductivity (EC), hardness, residual sodium carbonate (RSC) and adjusted sodium adsorptionratio (SARaj), were determined.The tunnels have been grouped according to the mineralogy present in the lithologies crossed by the water.The tunnels on the Northeast and the West of the island have the highest percentage of volcanic terrain lithologies, including basaltic lava and pyroclastic flows, where the main minerals are amphibole, olivine, augite,pyroxene plagioclase. However, the tunnels of the West cross lithologies with ignimbrites and epiclastic depositsand intramontane sediments, leading to an improvement in water quality compared to the Northeast cluster.This work shows that by drilling holes to search for fresh groundwater in volcanic terrain where surface lithologies can be identified, it is possible to estimate the water quality beforehand. PB Elsevier SN 1464-343X YR 2023 FD 2023 LK http://riull.ull.es/xmlui/handle/915/35688 UL http://riull.ull.es/xmlui/handle/915/35688 LA en DS Repositorio institucional de la Universidad de La Laguna RD 02-dic-2024