WATER IN THE EARTHS UPPER MANTLE

Experiments on the stability of hydrous minerals likely to be present in the Earth's mantle provide constraints on the distribution of water in the mantle, and the form in which it is stored. In regions of elevated mantle temperature, water may be stored not in minerals but in melts: such hydrous melts are important metasomatizing agents, and can induce volcanism beneath thick cratonic lithosphere.