Question

What is common of volcanoes that have the most violent eruptions?

Answer 1

High viscosity. It traps volcanic gases in these volcanoes.

Explanation:

Eruptive volcanes (or gray volcanoes) differ from effusive volcanoes due to their levels of viscosity, or how thick the magma is. Volcanoes of rhyolitic composition tend to be highly viscous, that is to say that the silicate to water ratio is higher than the others (about 7 to 1).

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