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View Full Version : Is it possible to control volcanic eruption with nukes?



Dommo
12-31-2008, 06:43 AM
First things first. I'm not saying that it's possible to stop an eruption. That's seems like an act of futility, delaying might be possible, but the longer the time between eruptions the more energy is stored in the magma chamber.

My idea is to keep a volcano's throat open so as to premptively cause an eruption. This way gasses/magma can escape out of the opening at a lower pressure, and keep the eruptions gentle and predictable(something analogous to the Hawaiian volcanoes). The reason I suggest using nukes, is that to be honest if you have to remove cubic kilometers of rock to make way for an opening, nukes are pretty much the only way to do it(especially if removing said rock would cause an eruption immediately after).

So what's the point? The objective is to replace very seldom but very destructive eruptions(ala Mount Saint Helens or the Super Volcanoes like Yellowstone), with more frequent, but less violent eruptions(like the Hawaiian volcanoes). You do this by ensuring that pressure never builds up to really dangerous levels by allowing for the pressurised gases/magma to escape instead of get trapped under a cap of rock inside a volcano. In this way, it might be possible to create a sort of safety valve that could gradually reduce pressure in some of the worlds more dangerous volcanoes(yellowstone, northern new zealand, etc.).

Personally as someone living in the midwest, I'd rather have a small area destroyed by a huge lava lake forming, than a potential world wide disaster caused by the uncontrolled eruption of yellowstone or something. If it's possible to vent off the pressure than I think it is something that should be looked at, even if a little radioactive fallout is involved.

Pthom
01-01-2009, 02:13 AM
I suppose it is possible.

But wouldn't the resulting radioactive fall-out be as devastating as volcanic ash and a few noxious gasses in the atmosphere?

And I betcha dollars to doughnuts that you'll make several many enemies with the suggestion of lighting off a nuclear bomb in Yellowstone National Park!

Just saying. :D

petec
01-01-2009, 02:36 AM
If it's gonna blow let it blow.

do not make it worse

Dommo
01-01-2009, 07:05 AM
Nah the fallout wouldn't be that bad. Thermonuclear devices are relatively clean, and considering that they'd be buried deep in the ground when they go off, the fallout shouldn't be too big of an issue. I mean honestly consider how many nuclear tests we've done over the last 50 years, and the overall effects of the fallout have overall been pretty negligible.

I used to live out in washington state, and tacoma and seattle are doomed cities(both were constructed in the middle of historical lahars from mount rainier). If rainier ever erupts violently, which it will certainly do at some point, it will completely destroy tacoma and devastate seattle. Within an hour both cities will be buried in 40 feet of mud.

As things stand, both cities are living on borrowed time, and with rainier having a major eruption(one big enough to melt its glaciers) on average about every 500-1000 years or so, it's could very well happen again in our lifetimes. Should such an event happen, I wouldn't be shocked to see a death of over a 100,000 people, as there's simply no way to evacuate the areas in an hour's time.

JHillman
01-01-2009, 11:49 PM
Somehow I think this ranks up there with the question: Do you want to come out of hyperspace in the middle of a supernova or a black hole?

Pthom
01-02-2009, 02:53 AM
... If rainier ever erupts violently, which it will certainly do at some point, it will completely destroy Tacoma ...This wouldn't necessarily be a bad thing . . . ;)


Somehow I think this ranks up there with the question: Do you want to come out of hyperspace in the middle of a supernova or a black hole?:D

Dommo
01-02-2009, 03:09 AM
Of course a supernova is the answer to that question sheesh :P .

Ruv Draba
01-02-2009, 11:31 PM
My idea is to keep a volcano's throat open so as to premptively cause an eruption.Do you really want to release all the ash and sulphuric gasses into the air? While a supervolcanic (http://en.wikipedia.org/wiki/Supervolcano)explosion can kill people in a 60mi radius (so, millions of people), the aftermath of supervolcanic eruptions (e.g. ash in the atmosphere) have killed 90% of humanity in the past through Ice Age effects and destruction of food-sources, and created permanent changes to our atmosphere. It wouldn't just be hikers in Yellowstone grumpy with you -- most countries in the world would consider the attempt an act of irresponsibility, and the creation of a global ash cloud to be an act of war.

Dommo
01-03-2009, 03:25 AM
Ruv, by keeping the eruption small, there wouldn't be a super huge ash cloud because there wouldn't be enough stored energy to blast that much rock into the sky. That's the point of preempting the eruption. You allow the volcano to erupt, and bleed off the pressure being built up before it grows enough to cause a catastrophic eruption.

It's like removing a stopper on a tea kettle. If I keep heating the water(and the stopper won't come out), the kettle will blow up. However if I make sure the stopper is never on the kettle, the pressure can never grow enough to cause a truly catastrophic eruption.

Ruv Draba
01-05-2009, 01:59 PM
Dommo, you're running squares against cubes here. Squares are to do with surface area -- how much flatspace it takes to let energy out in safe flux levels. Cubes are to do with volumes -- how much energy is stored. The neck of a balloon is around a twentieth of its radius, but it still vents like a mofo when you let air out. The expressed air travels for 3-8 radiuses away. Ash is heavier, and when supervolcanoes blow, they pump it around 30mi into the atmosphere -- or around twice the radius of their magma chamber.

At a fumbling guess, you might need to simultaneously destroy a 30mi radius of crust 5mi thick (that's how thick it is) to quell Yellowstone at 'safe' venting levels, so that ash and debris only travel 1mi up, say. We could do the math on the explosive force required to bust a 3,000 sq mile crust 5mi deep, but it wouldn't surprise me if it took the whole of the world's nuclear arsenal (est. 34,000 weapons) to do that -- at 15,000 cubic miles of crust, it's only two per cubic mile of crust, so perhaps not even enough.

Then there's still the gases and the logistics of it all. We're not great at dealing with 5mi depth of crust presently, not to mention thousands of cubic mi of gases and black, acid rain. Oil holes for instance, are at most 3ft wide, and go down a maximum of 7-8mi, typically through mud. The average oil well depth presently is under a mile. Punching through stone strong enough to hold down magma pressures while delivering nukes -- and spacing them across thousands of square miles of terrain -- would seem tough to me. Best case on Yellowstone is around 20,000 years before its next eruption40,000 years late for the next eruption. We could easily have space colonisation time to order pizza in that time.

Then there's the supervolcanoes yet to be discovered or clocked.

Dommo
01-05-2009, 06:13 PM
But Ruv you're missing the point. You can let it vent like a mofo, if it hasn't pressurized to the point where it's going to cause a massive explosion. Take the balloon example. If you half inflate a baloon and release the pressure, it vents pretty gradually.

The difference in pressures is the key here. If there's only a fraction of the energy needed for a full eruption in the first place, venting now or in the near future could be pretty safe. You don't need to completely reopen yellowstone's caldera, just punch a hole in it so that the pressure can be relieved. It's analagous to a relief valve on a water heater. The relief valve isn't the same diameter as the waterheater is.

HeronW
01-05-2009, 06:28 PM
Isn't that what Old Faithful geyser does --venting after buildup? What about drilling other release vents?

Claudia Gray
01-05-2009, 07:41 PM
I don't think nuclear weapons have anything like the kind of power needed to operate on the scale of volcanic eruptions. The pressure isn't primarily building just beneath the earth's surface, after all; the larger pressure is coming from so deep within the earth that anything humans can do just can't affect it. Take into account the ecological disaster created by using nuclear weapons and you have a prime example of "making a bad situation worse."

Ruv Draba
01-05-2009, 10:45 PM
But Ruv you're missing the point. You can let it vent like a mofo, if it hasn't pressurized to the point where it's going to cause a massive explosion.My understanding is that with supervolcanoes, large reservoirs fill with magma, eventually melting the crust above them and that the squirting occurs due to the change in pressure atop them. In the case of Yellowstone, say, this occurs every 600,000 years and we're around 640,000 years into that cycle -- so we're 40,000 years overdue on a bigga badda boom there. If that's true, good luck with punching a teeny tiny hole in it. ;)


The relief valve isn't the same diameter as the waterheater is.Actually, that's an overflow valve, because hot water doesn't explode. A relief valve is on something like a pressure-cooker, in which steam build-up could otherwise turn it into a bomb. We're talking magma rather than steam. It's not compressible. All the same, let's do the math.

Assume that magma flows like honey and that the reservoir is hollow and empty. If it takes 600,000 years to fill the chamber, then it's filling at the rate of half an inch depth per year on average. (Yellowstone's crust can lift by as much as 8 inches in a single year though, so some yearly fill rates may be much larger than that). At 8in per year, you have a volume of billion cubic feet of magma to release per year (or about 500 million cubic feet if you like the half-inch estimate better). If you're happy for a billion cubic feet of magma per year to fountain 1,000 feet up into the air then you only need a hole around 1200 yards across. That would be some mountain you'd be making there!

On paper. But...

That's also smaller than the diameter of the calderas in many regular-sized volcanoes -- and those guys blow at times too. So what's going wrong?

The problem is in our assumptions: magma doesn't flow like honey; it flows like wax, cooling as it goes and creating its own obstructions -- in part, that's how burning calderas become smoking mountains. And Yellowstone's magma reservoir isn't a big, empty gourd; it's a maze of porous and hard rock with magma worming around between.

Presumably, you'd have to vent in lots of places through Yellowstone and somehow manage to keep those holes open (or because we live mayfly lives in geological terms you might let them cool and punch more later). Or just turn Yellowstone's crust into kibble -- a task for which the world's 34,000 nukes might not actually be enough. :D

And that's only if it weren't brim-full of magma and pent-up sulphide gases giggling at you and your drilling-rigs. :Shrug:

Dommo
01-08-2009, 09:12 AM
Use tandem nuclear shape charges. It is possible to focus the blast of a nuke in a specific direction.

Also Ruv you do have relief valves on waterheaters, because they are BOILERS! When you heat up water in a water heater, it builds a steam bubble in the top of the heater unless you have a relief valve to bleed off the steam. Back in the old days waterheaters used to not have them, and sometimes they would literally launch up like rockets and destroy houses.

So here's my Dr. Evil scheme. You set up a tandem shape charge MIRV.

1. Load up 1 Trident nuclear missile.
2. Set up the MIRV's so that they streak into the same spot 1 after another.
3. Have all the warheads be shape charged, 1 megaton weapons.
4. Drill said hole.

Who says you need to actually drill the hole :P? You simply scream in a bunch nukes and send them one after another into the hole the previous one made.

MelancholyMan
01-16-2009, 02:35 AM
No. You couldn't control it, but you might make it worse.

lpetrich
03-16-2009, 05:09 AM
Nuclear bombs are certainly very powerful, but are they powerful enough to do the excavation needed? We can calculate that.

From TNT equivalent (http://en.wikipedia.org/wiki/Kiloton), 1 gram of TNT releases about 4184 joules of energy when it explodes. A 1-megaton nuclear bomb will release 1012 times as much energy, or 4.184*1015 joules.

Volcanoes are several mi/km in size, so let's consider how much energy is needed to lift 1 cubic kilometer of rock 1 meter. That amount of rock has a mass of about 3*1012 kg, and lifting it thus requires 3*1013 joules.

So with full efficiency, a 1-megaton nuclear bomb will lift 1 cubic kilometer of rock about 100 m, which is not much compared to a typical volcano's size.

From underground nuclear testing (http://en.wikipedia.org/wiki/Underground_nuclear_testing), this bomb would have the following effects on nearby rocks:

Melt cavity: 40 - 120 m
Crushed zone: 300 - 400 m
Cracked zone: 800 - 1200 m
Zone of irreversible strain: 8000 - 11000 m

So a nuclear bomb would have only a rather localized effect on a volcano.

These distances scale as (explosive force)1/3, so a bigger bomb won't buy much.