Which mechanism causes felsic magma to exhibit higher explosivity during volcanic eruptions?

💡 Explanation

When felsic magma, rich in silica, ascends, its high viscosity hinders the escape of dissolved gases; this causes increasing pressure until explosive decompression occurs due to bubble nucleation. Therefore, higher viscosity determines explosivity, rather than lower solubility, crystallization or reduced water content requiring different magma properties.

• Which geological action primarily dictates the depth profile morphology of fjords during interglacial periods?
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• Which mechanism causes increased stream discharge variability in regions transitioning from glacial to fluvial drainage patterns?
• Which outcome directly limits phytoplankton growth after an upwelling event during summer stratification?
• Which outcome occurs when prolonged floodplain sedimentation exceeds levee accretion rates in fluvial systems?
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