Water content of the mantle beneath Changbaishan Volcano, NE China

Abstract

The water content of the source mantle is estimated for basaltic products from the Changbaishan volcano, NE China. Major element compositions of quenched glass inclusions in scoria samples were analyzed using EPMA, and the water contents of 0.15-3.5 wt.% were obtained by the difference of the analytical total of the major element analysis from 100 wt.%. Given that the highest H₂O/K₂O ratios of 0.9 represent that of the original water content of the melt without leakage, the water content of the source mantle is estimated to be ∼350 ppm, which is significantly higher than that of the normal depleted mantle (∼120 ppm; Salters and Stracke, 2004).