and effusive basaltic eruptions.The preceding repose period commands the SiO2 content of the first erupted magma, and at the same time the magnitude of the opening phase, i.e. the shorter the repose the smaller is the following eruption. The chemical composition of erupted
material also changes with time in the eruption. The opening phase has the highest SiO2 content and during the eruption, it lowers
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