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There is a great number of magmatic inclusions in different types of phenocrys-tals in andesitic lavas from the Krakatau volcano, Indonesia. Sequence of crystalliza-tion (from early to late) has been established for the phenocrystals on the basis of homogenization tempera-tures and chemical compositions of the magmatic inclusions: the cantral phase of plagioclase phenocrystals(An 83.2--72.6), olivine→ the intermediate phase of plagioclase phenocrystals (An 61.3), clinopyroxene,titanomagnetite→ the peripheral phase of plagioclase phenocrystals (An 54.4--42.6). The crystalliza-tion of the central phase of plagioclase phenocrystals takes place in the depth of magma chamber at about 5Kbar. High pressures and high titanium contents favor the silicate-liquid immiscibility in the magmaticinclusions of early plagioclase phenocrystals. This is typical of many andesitic lavas generated in subductionregions.
There is a great number of magmatic inclusions in different types of phenocrys-tals in andesitic lavas from the Krakatau volcano, Indonesia. Sequence of crystalliza tion (from early to late) has been established for the phenocrystals on the basis of homogenization tempera-tures and chemical compositions of the magmatic inclusions: the cantral phase of plagioclase phenocrystals (An 83.2-72.6), olivine → the intermediate phase of plagioclase phenocrystals (An 61.3), clinopyroxene, titanomagnetite → the peripheral phase of plagioclase phenocrystals (An 54.4 - 42.6). The crystalliza tion of the central phase of plagioclase phenocrystals takes place in the depth of magma chamber at about 5 K bar. High pressures and high titanium contents favor the silicate-liquid immiscibility in the magmatic inclusions of early plagioclase phenocrystals. This is typical of many andesitic lavas generated in subductionregions.