Which factor is the primary cause of eruption style variations among stratovolcanoes along subduction zones?

💡 Explanation

Eruption styles in stratovolcanoes vary because of differences in the magmatic composition that affects viscosity, controlling gas escape and eruption explosivity. Therefore magma silica content and viscosity is the primary driver, rather than mantle plume proximity, crustal thickness variations, or minor atmospheric effects.

• Which feedback mechanism explains higher sea surface temperatures that disrupt upwelling within an ocean gyre?
• Which mechanism initiates surface subsidence after rapid groundwater extraction in coastal aquifers?
• Which mechanism initiates thermohaline circulation when surface seawater freezes near polar regions?
• Which mechanism primarily determines the orientation (aspect) of a cirque on a mountain range?
• Which mechanism causes felsic magma to exhibit higher explosivity during volcanic eruptions?
• Which phenomenon is intensified when the ascending branch of a Hadley cell overlaps with a warm ocean current?