Water Retention Revealed in Mantle Xenoliths

Researchers led by Konstantinos Thomaidis and Jannick Ingrin have examined how mantle xenoliths retain their original water content during volcanic eruption and surface cooling. The work focuses on samples collected from Allègre and Ray Pic volcanoes in France’s Massif Central region, where xenoliths are exposed at the surface following lava flows ¹.

The scientists studied hydrous-point-defect pyroxenes—minerals that incorporate water molecules into their crystal lattice—to trace the water concentration originally present in the lithosphere ¹. They measured water contents across several xenoliths and compared them with theoretical models for how much water should be lost or altered during emplacement and cooling ¹.

The study was published in volume 38 of the European Journal of Mineralogy (pages 477–489) under DOI ² 2026. Co-authors include Etienne Deloule, Lydéric France, and Huan Chen ¹