On the Volumetry of Magma Reservoir as a Function of K₂O Content

Abstract

An attempt is made in this paper to estimate the volume of magma in primary stage of volcanic activity as a function of content of K₂O in a differentiating residual magma. In the test it is found that present method of volumetry (equation (1)) seems applicable in case of Usu Volcano in Hokkaido, Japan.