Coupled δ18O-δ17O and 87Sr/86Sr isotope compositions suggest a radiogenic and 18O-enriched magma source for Neapolitan volcanoes (Southern Italy)

Sr-O mixing models indicate that such magmas were derived from a mantle source that was contaminated by up to 10% of a 1:1 mixture of pelagic and carbonate sediments. These findings together demonstrate the highly complex and varied magma sources in the Campania volcanic district. Triple oxygen isotope variations (Δ17O), based on measurements of both 18O/16O and 17O/16O ratios in potential assimilants are in agreement with these conclusions.