Which volcanic outcome often results when rising magma encounters thick continental crust rich in silica?

💡 Explanation

When rising magma encounters silica-rich continental crust, increased magma viscosity occurs because silica polymers inhibit flow which promotes trapping of dissolved gasses, leading to explosive eruptions and the formation of stratovolcanoes. Therefore pyroclastic explosions forming composite volcanoes result, rather than effusive flows, caldera collapse, or cinder cones which require different magma properties.

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