Thermodynamic Settings of Melting and Melt Ascentfrom Magmatic Chambers Using the Example of Klyuchevskoi Volcano

摘要

Theoretical models and experimental data on the thermodynamic and rheological properties of basalts from the Apakhonchich lava flow (Klyuchevskoi Volcano, Kamchatka) were invoked for plotting pro-jections of water-containing and dry liquidus and solidus curves on the P_s-T plane. The P—T—X_(H_2O)condi-tions for the formation of basaltic magma and the degree of its differentiation were determined from data on melt inclusions. The calculated apparent viscosity of the melt containing 10% crystals at 1100℃, 1 GPa, and 3 wt % water is 1.1 x 10~3 Pa s, and the density is 2.5 g/cm~3.