How to make a volcano erupt on cue.
via Wired Science…
Okay, so, how would I do it? First, I need to find a volcano ready to erupt that doesn’t erupt frequently (so that pressure is already building).
If you want an explosive volcanic eruption, you want to produce bubbles (and lots of them) by (1) decompressing the magma, causing gases to come out of solution; (2) crystallizing minerals to concentrate water/volatiles in the remaining magma or (3) heating the magma with a new intrusion. A release in pressure can be accomplished a number of ways, including the failure of the roof above the magma body (a volcanic landslide is a great way), the buoyant rise of the magma or through some less common factors like melting of a glacier (likely too slow a process to trigger a specific eruption), excessive precipitation to erode the volcano, changes in atmospheric pressure or maybe even Earth tides caused by the pull of the Sun and Moon (rare, mostly in already active volcanoes). Once you’ve produced bubbles, you need to concentrate them towards the top of the magma body, maybe through a earthquake — think about shaking an open bottle of soda with bubbles on the side: They all float to the top. However, in all these cases, you likely need a volcano that is “primed” to erupt — that is, one that has eruptible magma that just needs to be “tipped” into erupting.
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