Volatiles and hydrogen isotopes of melt inclusions from Iceland volcanics

Abstract

To characterize the volatile components of the Icelandic plume, we collected picritic basalt from spatter, scoria, and subglacial pillow lava from a wide area of Iceland, and measured the volatile content and hydrogen isotope ratios of volcanic glass and melt inclusions in olivine. A negative correlation between water content and hydrogen isotope ratios is observed, suggesting that this correlation involved a mantle with lower water content and a higher D/H ratio than the upper mantle (dD ~ -40 per mill) and a mantle rich in water and with a lower D/H ratio than the upper mantle. Both mantle components may have a deep Earth origin, but further analytical analysis is required to clarify this.