Volcanoes triggering volcanoes?

There’s lots of volcanic action in the Aleutians arc at the moment, with three volcanoes: Okmok. Cleveland, and Kastochi, all erupting at various points in the last month or so.

Aleutiansvolc.jpg

The Volcanism Blog and the Eruptions blog have both been keeping us up to date with the waxing and waning of these eruptions. However,given my past interest in possible seismic triggering of volcanic eruptions, it’s possibly no surprise that I’ve been wondering whether the near-simultaneous eruption of three volcanoes in the same geographic region is entirely a coincidence. Could the eruption of one have triggered the others?


Note that this triggering does not involve causing a completely inactive volcano to suddenly reactivate; it’s more about pushing a volcano that is already building up to an eruption over the threshold a little earlier than it would have done otherwise. In this case, could the seismic energy released by the first eruption of Okmok on July 12th have provided that extra little push to Cleveland and Kasatochi needed? Out of curiousity, I used the reports from the Alaska Volcanic Observatory (see here, here, and here) to roughly plot the activity of the three volcanoes against each other.

Aleutiansvolcact.jpg

At first glance, there’s some evidence of a possible connection. Okmok has been erupting fairly continuously in the last few weeks, but there have been a few distinct periods of heightened seismic and eruptive activity (the thicker parts of the line). Cleveland’s latest eruption (one of a series that have occurred over the last couple of years, including this one) began on the 21st of July, 1-2 days after one of Okmok’s bursts of activity. Kasatochi erupted on August 6th, 4 days after another period of increased rumbling from Okmok on August 2nd. However, as we all know, correlation is not causation, and it all depends on the sort of timescales over which you’d expect a volcano to respond to a seismic jerk, and whether a few days reasonably falls within that range. I’m not so sure it’s not a little to long.
Additionally, you can also see from the above figure that the activity at Cleveland began to peter out on July 29th, right in the middle of another period of vigorous eruptive activity at Okmok. This stronger, negative, correlation seems to rule out the idea of any strong linkage between activity at these two volcanoes. Still, it was worth a look…

Categories: geology, volcanoes

Comments (13)

  1. Ron Schott says:

    I’m highly skeptical that there is any connection other than coincidence involved here. I don’t doubt the possibility (albeit remote – pardon the pun) of remote triggering if the seismic energy release had been significant and nearby (in time, and to a lesser extent space), but I doubt that the seismic energy released during one of these eruptions rivals that of a major earthquake. And if we’re talking regional correlations, do you see similar evidence in Kamchatka or elsewhere?
    Very clearly there is no basis for triggering based on shared magmatic plumbing – not that you suggested that, but I wanted to put a damper on that before anyone else did.

  2. John Pyke says:

    From my non-expert knowledge*, it seems unlikely that one eruption would do a lot to trigger another, but what I notice all the time on these volcano blogs is an unexpressed assumption that it’s all totally random and unpredictable – almost as if no causative mechanism is known or can be known.
    Now since volcanoes at plate collision areas are presumably caused by some of the material from a sinking plate – the lighter material, or at least that which won’t form a solid solution with the heavy siderophilic elements – separating out, I have a possibly naive question. Has anyone researched the correlation between ‘lurches’ in plate movement and the triggering of volcanoes? Has a thicker-than-average bit of oceanic plate been swallowed under the Aleutians ‘recently’ (in geological time units)? Is the eruption of Chaiten a delayed consequence of the great ‘lurch’ in that area in 1960? Or do plates just slide down, and magma separate out from them, slowly and at roughly-uniform speed, so that the only triggering factor is how much a magma ‘chamber’ can hold before it blows?
    (*I was a geophysicist once but of the ionospheric variety, not the plate-tectonic variety. Now I’m just a law lecturer who is fascinated – at a distance – by volcanoes.)

  3. RBH says:

    … it’s possibly no surprise that I’ve been wondering whether the near-simultaneous eruption of three volcanoes in the same geographic region is entirely a coincidence. Could the eruption of one have triggered the others?

    You may be interested to know that in The Voyage of the Beagle Darwin wondered the same thing about a sequence of earthquakes and volcanic eruptions that occurred while he was on the west coast of South America. :)

  4. Chris Rowan says:

    Yes indeed – it was reading a fictionalised account of Darwin’s observations that originally got me interested in this topic.

  5. thomas lombardi says:

    they probably are connected…..as is this!
    3 part investigative report…..NASA photos
    http://www.enterprisemission.com/_articles/05-14-2004_Interplanetary_Part_1/Interplanetary_1.htm

  6. Maria says:

    That report is hyperdimensional! Wow, that sounds really sciencey! I’m totally impressed.
    Anyway, yes, people have researched earthquake triggering of volcanic eruptions. It definitely happens, on timescales of zero to a couple of days, but we’re not entirely sure what the mechanism is – since at most 0.4% of eruptions are triggered by earthquakes there are not many opportunities to study the process in the wild.
    Warner Marzocchi has promoted the idea that as the upper mantle relaxes after an earthquake it can produce eruptions, with a timescale of decades between earthquake and eruption. I’m not sure I buy it – the stresses involved are fairly small – but it’s not ridiculous. Without looking at it in detail I don’t know if it would be plausible for Chaiten or not. However, the 1960 earthquake did trigger an eruption at Cordon Caulle two days later.
    Chris, the real problem with your hypothesis is that there haven’t been any large earthquakes associated with these eruptions. Maybe I’m wrong about this but I don’t think volcanic tremor is high enough amplitude to do much.

  7. Chris Rowan says:

    Maria – you’re probably right that there’s been no activity of the right sort of magnitude to have anything other than very local effects. But I thought it was worth a look in a vaguely sciency manner, even if the final answer was ‘probably not’.
    Of course, I forgot to check out the hyperdimensional activity with my tricorder, so perhaps I missed something.
    As for Marzocchi, I’ve read some of his stuff and I think the problem is he’s looking for significant correlations in a very small dataset. So even if he’s onto something, it’s really hard to tell.

  8. Thanos says:

    Does the interelation need to be seismic? 1998 through the present there anecdotally seems to be more vulcanism at both poles. I call it anecdotal because I normally don’t follow this stuff, but have seen more news stories during that period. That could be due to more focus on those regions (IGY polar, etc.) or actual increased activity. As an amateur I haven’t a clue.
    But back to the question – thinking in terms of fluids under pressure in a ballon, and bubbles. If parts of the fluid core were hotter than others due to localized reactions could there be subsurface regions with higher pressure than others (answer yes in subduction zones, but what about due to localized heating?)Could pressure bubbles of magma travel? Not being even close to being a scientist, you are most welcome to shoot my musing down in flames.

  9. Old Bogus says:

    I would see any causality between them more along the lines of one relieving the stress along a section of the subduction zone, allowing the next section to press the next magma chamber and it popping like a pimple. Or some such metaphor.

  10. cabbagepow says:

    I’m not sure I buy it – the stresses involved are fairly small – but it’s not ridiculous. Without looking at it in detail I don’t know if it would be plausible for Chaiten or not. However, the 1960 earthquake did trigger an eruption at Cordon Caulle two days later.

  11. zayıflama says:

    I call it anecdotal because I normally don’t follow this stuff, but have seen more news stories during that period.

  12. Diyet says:

    If parts of the fluid core were hotter than others due to localized reactions could there be subsurface regions with higher pressure than others (

  13. zayıflama says:

    I don’t think volcanic tremor is high enough amplitude to do much.