发育在斑晶内部的熔体包裹体可以保存斑晶形成时的水含量而不受后期去气等作用的扰动,因此可以被用来研究喷发前的岩浆水含量。然而众多研究均发现,在橄榄石熔体包裹体中存在H+扩散的现象:即随着岩浆的上涌减压,去气作用会使得环境中熔体水含量下降,因而H+会从熔体包裹体向外部熔体扩散以达到一个新的平衡,其扩散速率在很多研究中足以影 The melt inclusions in the interior of the plaque can preserve the water content during the formation of the porphyrite without being disturbed by the later degassing and so on. Therefore, it can be used to study the magmatic water content before the eruption. However, many studies have found that there is the phenomenon of H diffusion in the olivine melt inclusions: as the magma up-down decompression, de-aeration will make the melt water content decreased, so H + will melt from the package The bulk diffuses to the external melt to reach a new equilibrium whose diffusion rate is sufficient in many studies