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Science

Undersea Deposits of Frozen Methane Found 411

geoswan writes "The CBC is running a story about large deposits of Frozen methane off the coast of Vancouver Island . The deposits may be 850 meters deep. The story doesn't say how the methane came to be a solid. Pressure? The story doesn't address what technology could be used to mine these deposits, if the decision is made to develop these resources. The CBC showed pictures taken of the methane hydrate. Sure enough, it looked like a big snowbank. It is an environmentally sensitive area. So, how about it, should it be exploited?"
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Undersea Deposits of Frozen Methane Found

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  • Who owns it? (Score:2, Interesting)

    by Anonymous Coward
    Who owns the area where the deposit is? Is it owned by Canada, or is it in International waters? And how will they decide who gets to "exploit" if they decide to?
    • Re:Who owns it? (Score:4, Informative)

      by Shab264 ( 556637 ) on Tuesday September 10, 2002 @08:34AM (#4227396)
      It doesn't matter who owns it right now...because with current mining and salvage technology, that deposit of hydrates is a liability and nothing more. Right now, there's no way of safely and efficiently getting all that gas from the bottom of the ocean. If you went down there and hit a big chunk of that stuff with a pick axe, you'd risk setting off a chain reaction that could lead to a catastrophic explosion (no kidding...I wrote a research paper on methane hydrates for my degree) that could spell disaster for the whole world...(methane is about 50 times more potent as a greenhouse gas than CO2)...or at the very least kill everyone at the site either by suffocation or fireball. Even if you gently try to scoop the stuff up and bring it to the surface, it will decompose on the way up and either suffocate everyone at the site or ignite and burn everyone to death. There's been several times already where an oil derrick was engulfed in flames because the hydrates around the site became unstable, bubbled to the surface and met up with a happy spark.

      The point of all this informative rant: hydrates hold the world's most ginourmous amount of natural gas--but if you mess with it with current technology, you can release it all at once and really screw the earth up.
  • Bermuda Triangle (Score:5, Interesting)

    by simetra ( 155655 ) on Tuesday September 10, 2002 @06:39AM (#4226741) Homepage Journal
    I saw this on tv; there's butt-loads of solid methane on the sea floor in the Bermuda Triangle area. One theory of the vanishing planes is that the gas bubbles up to the surface and creates a big area of methane gas above the surface. The planes flew into the gas, and their engines ignited the gas, blowing them up. Possibly the same scenario with vanishing boats. I forget how the layer of solid methane got there, but apparently this is common in many places around the world.
    • Re:Bermuda Triangle (Score:5, Interesting)

      by squaretorus ( 459130 ) on Tuesday September 10, 2002 @06:47AM (#4226772) Homepage Journal
      Bermuda Info here [scientium.com] relating to this:

      Gas hydrates are formed when gases are trapped, under pressure and at low temperature (as at the bottom of the ocean), and dissolved in a frozen liquid. In this case, the gases are natural methanes -- the gas we use to heat our homes. These frozen gas hydrates are stable until higher temperatures or lower pressures cause them to decompose (melt). This decomposition releases enormous amounts of trapped gas.
    • Re:Bermuda Triangle (Score:2, Informative)

      by Anonymous Coward
      With ships it is a little different. The gas bubbles decrease the density of the water and therefore decrease the buoyancy of the ship. If there is enough gas bubbles in the water the ship does no longer swim and simply sinks.
    • I saw that show as well. However, the whole Bermuda Triangle thing is just a media-propagated myth. The number of ship wrecks and plane crashes in that area is no greater than would be statistically expected. The fact that some disappearances have never been explained is unremarkable; that's the nature of disasters at sea.

      The Triangle is no different than any other patch of ocean that has comparable sea and air traffic.

      Lloyd's of London [lloydsoflondon.co.uk], for instance, charges no extra premium for ships passing through the area. It's not considered high risk.

      To address your original point, though, it is still largely a theoretical phenomenon. There is no proof that methane bubbles have ever destroyed a ship (or plane, for that matter).

      • But they have sunk oil rigs, or at least large quantites of gas have. It's not theoretical.
        • Re:Bermuda Triangle (Score:2, Interesting)

          by bolie ( 39110 )
          That's when the rig hit a pocket of "shallow gas" and ruptured it or disturbed it, sending massive quantities of gas to the surface at once. The gas bubbles reduce the density of water and the rig sinks. The water is so foamy you can't swim in it, either.

          Bolie IV
    • The planes flew into the gas, and their engines ignited the gas, blowing them up. Possibly the same scenario with vanishing boats.

      Bubbles of methane would drastically reduce the density of the ocean around a ship, causing it to sink... by the time the methane had dissipated into the atmosphere, the hull would already be below the waterline and would be covered by the water filling the holes previously occupied by the gas.
    • BBC has an article [bbc.co.uk] about a possibly similar incident in the North Sea.
      • by arivanov ( 12034 )
        Besides the article it has also been broadcasted in BBC series on global warming. Few notes: 1. It is not frozen - it is gaz-hidrate. Which is natural under the pressure+temperature conditions in question. It is though that there is a humongous quantity of methane tied in gas-hidrate on the ocean floor especially where rivers bring out organic matter into the ocean. 2. If you look into the global warming models - half of them do not account for this methane and methane has higher greenhouse effect than carbon dioxide. The ones that take into account this methane in general predict hell on earth. Basically once the ocean has warmed up enough the methane starts to come out which speeds up global warming and more methane comes out. Classic chain reaction. 3. There is some geological evidence that these methane eruption global warming events have happened in the past. It was presented on the BBC program in question. 4. Forgot how the show was called but it is possible that you may find some of the data on bbc web site (not news, the proper www.bbc.co.uk).
    • I saw that show as well (Discovery?)...and the video of the upwelling by that oil rig was incredible....you don't often see fire in and below water. :)

      However, as I recall it wasn't frozen methane, it was large amounts of methane trapped in rock....so much that the rocks could actually be ignited and burn. I don't know if that really changes anything...but it wasn't actually frozen methane.
    • Heh, "butt loads" of methane. What a strangely appropriate measure.
    • Re:Bermuda Triangle (Score:3, Interesting)

      by geoswan ( 316494 )
      Here is a press release [communications.uvic.ca] and some photos [communications.uvic.ca], and a background sidebar [communications.uvic.ca] methane hydrate.

      Michael Whiticar, one of the principal researchers, was interviewed on CBC newsworld at noon today.

      In this interview he said that while there are other undersea methane hydrate ice in other parts of the world, this site is unique. If I heard him properly, its size dwarfed other sites. If I heard him properly, other sites are formed by biological activity, whereas this was due to the leaking of petroleum fractions.

  • by Anonymous Coward on Tuesday September 10, 2002 @06:39AM (#4226742)
    ...as if millions of trolls cried out with bad fart jokes for this topic... ;)
  • by Powercntrl ( 458442 ) on Tuesday September 10, 2002 @06:40AM (#4226743) Homepage
    "Holy flammable gas Batman, did they just say methane on Slashdot?"
    "Yes they did Robin, you know what that means."
    "Links to goatse! Oh the horror!"
    "Yes, and we haven't much time to lose. To the Batmobile!"

  • by nesneros ( 214571 ) on Tuesday September 10, 2002 @06:41AM (#4226746) Homepage
    You know, we have something like 15 millian cows in the US alone, and we haven't even begun to milk that source yet, why go to the bottom of the ocean for it?

    Other sources include:

    1) Our office after Qdobo's 2 for $2 Thursday night burrito special.
    2) My uncle Floyd.
    3) The United States Congress.
  • Not new (Score:3, Interesting)

    by Anonymous Coward on Tuesday September 10, 2002 @06:41AM (#4226750)
    There's more of this stuff in the North Sea -- I've seen a cool film clip where a scientist takes a chunk of it and sets it on fire!

    However, the last time I heard of these deposits, some folks were worried that mining them would destabilise the mass, causing an uncontrolled release of ENORMOUS quantities of methane. Which would mean bad things for the environment, what with methane being a greenhouse gas, and all.

    ...by ENORMOUS, I mean quantities larger than gets released in decades of industrial/agricultural activity. Vast vast vast amounts.
    • Re:Not new (Score:2, Interesting)

      by SEWilco ( 27983 )
      Yes, methane hydrates are old news. There are a lot of them -- some seem to be trapped methane caused by bacteria, although much of it happens near known oil and gas deposits [tamu.edu] and are simply due to methane being trapped as it leaks toward the surface.

      Of course, the risk of these deposits is in the uncontrolled release of methane. It would be good if we can mine them and turn them into the less dangerous carbon dioxide.

      After all, if we don't mine them some of them will evaporate anyway. Volcanic action, a rock from space, a sunken ship or fisherman's net scraping across...or simply a low-pressure hurricane crossing a deposit which has expanded to its upper limit.

      For that matter, those deposits which don't evaporate...what can they do? Get trapped under layers of sediment? Evaporate when the ocean floor folds into a mountain top? Get sucked back into the planet at the end of the tectonic plate, and be emitted from a volcano or leakage to the surface? It all reaches the surface sometime.

  • Note frozen methane (Score:5, Informative)

    by stevelinton ( 4044 ) <sal@dcs.st-and.ac.uk> on Tuesday September 10, 2002 @06:43AM (#4226754) Homepage
    It's not actually frozen methane as such. The freezing point of methane is much too cold for that. It's a clathrate essentially a form of ice with methane molecules trapped among the water molecules. It's stable at temperatures just above the normal freezing point of water, and high pressures. If the pressure is released (for example by bringing it to the surface) it decomposes into water and methane gas.
  • PV=nRT? (Score:2, Informative)

    by thogard ( 43403 )
    Most living things produce some methane. At depth, the pressure is high, the temp is about 4 degrees and methane will freeze solid just by the water pressure since its on the solid side of the triple point .

    There is a huge amount of frozen methane over most of the ocean but only where its about 1000m deep. If you can find a way to get it out at lower cost than oil, you can put opec out of business.
  • I hope this doesn't kill any renewable energy projects that Canada has in the works. Yes, this will buy them more time but they, like the rest of the world will wake up one morning and discover that the fossil fuels are gone. Sooner than most people realize. No, I don't own a hybrid car, and no, my house isn't solar powered. But I do think that GM [slashdot.org] has the right idea (shockingly!)

    Jumpin' Jack Flash, it's a gas, gas, gas!
  • Bermuda Triangle (Score:2, Interesting)

    by rgoer ( 521471 )
    Someone claimed to have found a similar phenomenon off the coast of Florida, around where the fabled "Bermuda Triangle" was supposed to be. Theory went: every now and then, seismic activity would crack the methane crystal, releasing some methane gas in the process. This now-liberated methane bubble would rise to the surface, and everything was cool if its path toward the atmosphere was free of obstacles like boats or planes... however, on the off-chance that a ship might be passing right by where the methane was surfacing, that ship would become unable to maintain buoyancy--as it now rested on a bubble of gas instead of a blanket of seawater--and would go down. Same thing for the planes: if the methane bubble, which has become more of a loose cloud now that it's free of the ocean, happens to be in the path of an airplane, that plane will dramatically lose almost all lift from its wings (since they're made to be working lift from normal air, which is much heavier than methane), and it, too, hits the sea. Weird.
  • armageddon (Score:5, Interesting)

    by jukal ( 523582 ) on Tuesday September 10, 2002 @06:48AM (#4226778) Journal
    If you want to get another source to fuel your paranoia and fears, read how release of underwater frozen methane [tripod.com] could cause armageddon :)

    "Has frozen methane ever been released before? 55 million years ago, 20% of the world's frozen methane reserves melted. This sparked cataclysmic changes in the atmosphere: global temperatures rose by 13 degrees Fahrenheit, melting the ice cps and forcing many species to extinction. 80% of all deep-sea creatures became extinct, and there were severe consequences for land animals. If vast amounts of methane were released, the highly explosive gas would be ignited by lightning, scorching huge area in a fiery hell-on-earth."

    Now, do you want them to touch it? :))

    • If it is such a harzard, shoudn't we try to develope a safe way of using this gas instead of waiting until it releases it self naturaly?

    • by stereoroid ( 234317 ) on Tuesday September 10, 2002 @07:04AM (#4226838) Homepage Journal

      This is a SF novel from 1994 which covers exactly this scenario. The long-term effects of global warming include the melting of the ice caps, as we know, but this book is about the shorter-term effects. An overall rise in the sea temperature, due to a huge release of clathrate methane, enlarges the hurricane-spawing areas of the ocean (areas above 27C). The result is larger and larger hurricanes, until, well, you can guess the rest from the title.

      Reviews: here [nesfa.org] and here [well.com].

      Ouch. Do you still want to touch those deposits?

    • Good idea (Score:3, Funny)

      by jmu1 ( 183541 )
      Hey, I say it's a great idea. Why manufacture weapons of mass destruction, when we could just have nature do it for us? I say go for it! Kill the world and have it done with.
    • A site with more information is here [spacedaily.com].

      Here [climateark.org] is a paper about how frozen methane may offer hope as alternate fuel
    • by Lumpy ( 12016 ) on Tuesday September 10, 2002 @07:31AM (#4226968) Homepage
      Now, do you want them to touch it? :))

      after that ... you bet your arse I want them to touch it, or at least figure out how to release it in a contained way so we dont get a cataclysmic release during the next earthquake in that area. or it builds up to a critical mass that self releases.

      basically it can be captured if you can force a slowish release of the gas you can easily capture it with a collection dome of some type and gas pumps to siphon off the gasses. a high rate release (I mean slow as in only a few thousand cubic meters of gas an hour.. I mean high-rate as in 30-40 million cubic meters of gas per second... IE: the planet farts) would generate more pressure and power than any man made device could handle or contain.. a steel collection dome would rupture instantly.

      Although another way would be to pump tons of Oxygen down there into the "snowbank" and set it all off underwater with explosives... Sure it would create a tsunami that would pale in comparasion to a gigantic metor crashing into the ocean but it would be really cool to watch! and imagine the TV shows about it.... "Survivor XII.... who will survive in these tiny rafts in the vacinity of the methane detonation"
    • by gmkeegan ( 160779 ) <gmkeegan@yahoIIIo.com minus threevowels> on Tuesday September 10, 2002 @07:39AM (#4227022)
      If vast amounts of methane were released, the highly explosive gas would be ignited by lightning, scorching huge area in a fiery hell-on-earth."

      We'd better start putting corks [vgernet.net] in the millions of cattle [ru.ac.za] all over the world [megastories.com] then.
  • Sure enough, it looked like a big snowbank. It is an environmentally sensitive area. So, how about it, should it be exploited?"

    In a word: No.

    Why create new risk for environmental damage when CONSERVATION (a reduction in Western Consumption) would prolong our existing (already bad) sources of pollution?

    I will never 'support' additional non-renewable energy creation (bc it causes more(any) pollution) while disposable toys/packaging comes with childrens meals, while everyone drives a SUV (that seats seven but never contains more than 1), while western consumer culture encourages disposable-worthless garbage be created (and wastes our existing 'energy' and 'pollutes needlessly')

    Basically, until we learn to use what we have wisely - and reduce our consumption (pollution generation) to a more natural balance, we cannot continue to dig up more and more and more and more and more crap we dont *REALLY* need... unless we want to make the planet toxic beyond our ability to live on it... and btw, this is a finite limit, a real 'destination' we are straight on course for.. the question is when do we get there.

    • So, how about it, should it be exploited?

      Absolutely. Any other organism on the planet with a use for this stuff and access to it would be exploiting the shit out of it without a second thought. Hell, most of these organisms wouldn't even give it a first thought, being motivated purely by biochemical imperatives. Why should we be any different?

  • by kris ( 824 )
    More information on Methane Hydrates on the continental shelves can be found at TECFLUX at Geomar [geomar.de]. Find the photo galleries here [geomar.de].

    The TECFLUX (TECtonically- induced FLUXes) project is a German-American effort dedicated to the long-term study of continental margin gas hydrates on Hydrate Ridge, Oregon. This multi-stage research project was based on more than a decade of research on the Oregon accretionary margin and on recent results from Sonne cruises 109 and 110. During these cruises massive hydrate deposits were recovered from nearsurface sediments; and sites where fresh water and methane gas from hydrate decomposition were documented. This newly discovered site lies less than 50 miles due west of Newport, OR, making it very accessible for detailed study. This setting is a perfect natural laboratory for the study hydrate formation and decomposition in continental margin.
  • by budalite ( 454527 ) on Tuesday September 10, 2002 @06:51AM (#4226787)
    Remember that scene in the movie "Paint Your Wagon" where, during a funeral service at a burial site in the Old West, gold was discovered at the bottom of the 6' hole? I vividly remember people jumping in with shovels and the corpse (wrapped in a sail) flying out. I thought that was pretty funny then. I still do. I think the chances of that area remaining pristine are directly and inversely proportional to the amount of money to be made from that deposit.
    To seque a little, how should (or can ) one decide objectively/mathimatically between short-term and long-term benefits?

    • To seque a little, how should (or can ) one decide objectively/mathimatically between short-term and long-term benefits?

      The economists answer to this is to deflate future benefits by whatever the "zero risk" interest rate may be. Thus long term returns have to pay more, when they do pay, than the same amount of money left in a bank account.

      The trouble with this is that it says that, for example, it is not economically worth saving the whales. According the this theory, we should simply slaughter the wales now, then invest the returns in something "useful".

      Now, I cannot prove it mathematically, but to me this is wrong. But that is an emotional response.

      So my real response is that you cannot objectively decide between short and long tem benefits. By all means do the economic calculations; look at what you are forgoeing on one plan for .benefits in the other. But allow non-financial factors to affect your decision. As well as, not instead of, financial considerations.

  • Bad news... (Score:4, Funny)

    by manon ( 112081 ) <.slashdot. .at. .menteb.org.> on Tuesday September 10, 2002 @07:08AM (#4226854) Homepage Journal
    This is bad news for Canada... Bush is going to want the land now...
  • 850 metres (Score:2, Informative)

    by Seska ( 253960 )
    Just to be clear, the article states that the methane deposits are under 850 metres of water, not that the deposits themselves are 850 metres thick.
  • how did they know? (Score:2, Interesting)

    by squarefish ( 561836 )
    I used to work as a fi$herman on large trawlers [americanseafoods.com] in Ala$ka and I'll tell you first hand that anything that wasn't the fi$h we wanted was immediately thrown overboard, with rare exception- fi$h is where the money is. It's hard for me to believe that a deckhand would actually pay attention to something that must have resembled a rock or piece of ice, but then again I bet boats have been pulling this stuff up for a very long time and it went ignored just for that reason.
  • Knowing human ingenuity (and greed factor), if there's a way to /e/x/p/l/o/i/t tap into it as an energy source, it will be done.

    Then again, it gives a whole new meaning to the phrase....
    Cap'n! She's gonna blow!
    • "Cap'n, I don't know how much longer I can hold her togetha! We're running out of methane hydrate crystals!"

      Seriously though, I hate to sound like I don't care, but the Earth isn't going to last as a stable ecosystem for humans. The face of the planet has, without the help of outside(living) forces, been completely decimated. So, why not take full advantage? Besides which, I do not look forward to any afterlife, therefore, I don't see much of a fear of 'raping' the Earth. I say go for it, the world is going to get worse before it gets better. :S

  • Refilling oil wells (Score:2, Interesting)

    by randomErr ( 172078 )
    There's been a series of stories about oil wells refilling themselves lately. One of the ideas is that our current source of oil is from methane that was trapped beneath the Earth's surface at the big bang, and from fosilized animals. This story could actually be further evidence of that idea.

    An alternate theory is that their is a biomass layer bacteria below the surface of the Earth that is producing methane. That methane is then changed into oil by heat, preasure, and the filtration to the surface of the. Haven't you noticed that most oil well are dug where there is a large amount of sandstone and other porous rock?

    <Useful links>
    http://www.wired.com/wired/archive/8.07/gold_pr.ht ml [wired.com]
    http://people.cornell.edu/pages/tg21/recharging/ [cornell.edu]
    http://www.csun.edu/~vcgeo005/Energy.html [csun.edu]
    http://www.people.cornell.edu/pages/tg21/origins.h tml [cornell.edu]
    http://www.amazon.co.uk/exec/obidos/ASIN/038798546 8/202-8329969-5193459 [amazon.co.uk]
    http://www.ldeo.columbia.edu/margins/seeps_worksho p.html [columbia.edu]
    • Another, non-crackpot idea is that the geology (i.e. rock formations) of oil well sites is somewhat more complicated than the well owners have realized, and that the finite amount of oil down there can move around under the huge pressures involved.

      The fact that petroleum tends to accumulate in porous rock layers is no more mysterious than the fact that liquid water tends to accumulate in porous rock layers. I can soak up more water with a sponge than with a stone, too.

      Neither means there is some quasi-unlimited source of petroleum down there.
  • Methane Hydrates (Score:3, Interesting)

    by practical007 ( 543562 ) on Tuesday September 10, 2002 @07:58AM (#4227137)
    Methane is hydrophyllic under certain pressure and temperature regimes. It can easily form a slushy substance known as methane hydrates. These are not only a resource, but commonly a production problem in deepwater (5000') offshore environments where flowing temperatures are low. They can form in lines and plug things up. I am doing an undergrad project on these and I have friends doing grad work on them as well. It's neat stuff, and the vast quantities mean a tremendous future for good ole clean burning natural gas. Wanna see something really amazing? Check out the methane resources beleived to be associated with geothermal brines.
  • I saw a report on the global warming flash points within earth. Basically the idea traced the carbon output of rainforests. Geologically global warming was gradual but intensived at certain time periods. These time periods were centered around forest fires in the rain forest areas. The general map is this. Rain forests can only act as a carbon sink for so much carbon before the dead material created by the forest begins to add to carbon output instead of the plants breath cycle decreasing it. In natural historic global warming (without man made intervention) the increase of life on earth slowly moved carbon distribtion until the atmosphere warmed this slow warm hyper excelerated in the last phases. This caused quick changes in temperature followed by a dramatic cold period. The key was the current rain forest model. It appears rain forests hold more carbon than predicted. In tracing this carbon it was found that dead organic material was carried by the rivers and decayed producing methane. But instead of the gas being released in the atmosphere this material was pushed into the sea depths and froze. Methan ice packs have been hit by oil drilling before and than come up a boil. The theory is that this extra carbon sink accounts for the rapid period of global warming in the geological evidence. Slow global warming slowly raises the rates of forest fires releasing more carbon from the forests when temperatures hit a point of affectin sea temperatures the methane in the ocean becomes gas. These large storages are dumped almost instantly creating a dramatic and quick rise in temperature which melts the ice caps and glaciers. This changes the saline levels of the ocean changing the heat distribution of the currents and flipping into a cold period. So it is best to not bring up these carbon sinks but to leave them untouched. Again the drive should be to move away from carbon based fuel. Related links
    http://news.nationalgeographic.com/news/2001/12/12 18_earthbelch.html [nationalgeographic.com]
    http://www.spacedaily.com/news/early-earth-01k.htm l [spacedaily.com]
    http://www.hydrogen.co.uk/h2_now/journal/articles/ 3_Methane.htm [hydrogen.co.uk]
    http://superstringtheory.com/forum/warmboard/messa ges2/116.html [superstringtheory.com]
  • IOn fact these are treated as drilling hazards witht tendency to explode when penetrated. Only recently have drillers become more confident in technology to produce them. Transport of product is still a problem. Very few natural gas ships. Most is by pipeline.
  • Why on Earth would we need to spend millions of dollars to find out how to mine the stuff when we are already producing plenty of the stuff? Every rubbish dump on earth is producing methane as a side product from the decomposing waste. Surely it would be cheaper and more ecologicaly sound to use that as a source of methane? The frozen methane is best left where it is, otherwise who knows what additional environmental issues why might face?
  • Um. Why? (Score:4, Interesting)

    by Agermain ( 255096 ) on Tuesday September 10, 2002 @08:36AM (#4227407)
    We have plenty of methane that doesn't even need to be mined. Most public landfills have to vent methane properly to prevent explosions. With the right business model, I'm sure state & local governments could use income from selling off methane to be refined into an energy source [virginia.edu] Hell, even the EPA [epa.gov] supports this course of action. Why bother with underwater mining, when it's practically in our own backyards [environmen...mistry.com]?
    • People are actually already doing this. In my home town, the fairgrounds are built on top of the old city dump. They use the methane taken from wells to heat the various buildings on the site (show barns, offices, ect...). The technology to do it isn't that complex; all you have to do is filter it properly.
    • I don't know where you're from, but over here, they DO extract methane from the landfill, and they use it to run a generator, and generate electricity for a small town whose main industry is a Foster Farms chicken plant.

      If they had a website, I'd link it for you.

    • Collection of Methane from old landfills is quite common in NW Europe.
      Often (usually) it is used to drive a generator via a Diesel engine.
  • by Anonymous Coward
    They are talking about Methane Hydrate. There is no way methane can be frozen solid at the range of temperatures and pressures found in the ocean floor. It will be above it's critical temperature.

    More information can be found under methane hydrate in google or:

    article [llnl.gov]

    among other. It's really an interesting compound and future power source.

  • Gas hydrates isn't just a methane thing. Other gases can get caught up in it as well.

    Actually, the gas molecules get trapped within a cage of water molecules. Depending on pressure, this can happen above the usual temperature where water freezes. In deep sea drilling, this can cause things to ice up, even in fairly warm water, if the pressure is high enough.

    The result can be costly in terms of money (processing equipment not working or hydrates clogging up pipelines, for example), or costly in terms of human lives. Blow-out preventer valves can freeze in the "open" position, giving a false sense of security, or hydrate plugs can clog up pipes, until they shoot off down the pipe as the pressure builds up on one side, eventually arriving like a projectile at the other end. The Piper Alpha fire in the North Sea was caused partially by gas hydrates preventing safety valves from closing.

    Gas hydrates can be very problematic, and chemicals such as methanol (called inhibitors) are routinely added to the oil/water/gas mix that is pumped up to prevent the buildup of gas hydrates.

    On the other hand, they can also be used to store gas. One volume unit of gas hydrate can be separated into 179 volume units of gas and 0.8 volume units of water.

    Gas hydrates are fairly common in the ocean floor. In fact, the largest land/mud/ocean floor slide known to man, off the coast of Norway about 7000 years ago, is suspected to have been caused by melting gas hydrates releasing their "grip" on the sand.

  • Remember that methane is one of the most common gasses in the solar system - the gas giants are largely made of methane. During the formation of the Earth a lot of gasses got trapped in it and it is constantly outgassing.

    "...the great earthquake in San Francisco in 1906 was accompanied by large fires, and it was said at the time that this was due to the fracture of gas pipes in the ground. That may well have been the case; however flames were also seen on hills nearby that had no gas pipes and also on roads and fields in nearby San Jose. The Armenian earthquake of 1990 showed a line of burnt bushes along a visible faultline."
    (quoted from Thomas Gold [cornell.edu])

    When this happens on the ocean floor the methane may combine with water under high pressure and low temperatures to make "methane ice" and chemosynthetic bacteria and methane ice worms [psu.edu] live in it!
  • How does methane actually cause greenhouse effect? It's not the burning of the methane, which creates only a small quantity of CO2 per KJoule. It's the methane itself, which, during the course of extraction, distribution and usage, will inevitable escape into the atmosphere. And methane is a MUCH more effective greenhouse gas than CO2!

    BTW, that's why the cows in US and India do, in fact, contribute to the greenhouse effect quite considerably.

  • This is the kind of news story that always appears at the beginning of a Gozilla movie.

    Save Tokyo!
    Do not disturb the frozen methane!
  • The deposit of methane hydrate, or frozen gas, came to light early last month when a fishing crew pulled up a chunk of the material in their nets.
    How could they pull a chunk of pure methane hydrate to the surface without it decomposing? It breaks down when you reduce the pressure.

    It could be rocks saturated with methane, similar to those found under the North Sea - but if that's the case, the deposit itself is practically worthless (how much rock would have to be brought to the surface and crushed/heated/whatever in order to release the methane?)

    More likely, these are just (again as in the North Sea) just an indicator that there are deeper reserves of oil and/or gas below the seafloor, and little to do with methane hydrates.

    For that matter, althought he article says 'in about 850 metres of water', the text on the picture shows '850 metres below the ocean floor' - NOT the same thing.
  • There's a much larger concern that should be addressed: Being underwater, it's fairly safe from melting, partly due to pressure from surrounding seawater... But now that it's known to be there, it would be more in their interest to remove it... I'm not too sure of whether or not it would float if somehow it broke free of the seabed, but in the event of a sizable earthquake in the area (as it appears to lie on a major faultline)... Could it be dislodged, resulting in it's breaking free, rising to the surface and evaporating into gaseous form, adding to the abundance of already existing greenhouse gasses?

    Secondly, there are ways to mine the material without disrupting the surrounding environment... In fact, it has the potential be the first deep sea industry... A hypothetical scenario could involve deep sea submersables designed to saw away at the ice, stowing the material in cargo carriers that could then be lifted to the surface for later processing on land, complete with a smallish base for crew, management and control systems... With enough effort, it could even be automated for safety's sake...

    Just my 3.4 cents (adjusted for Canadian dollar)...
  • ...it is methane hydrate. That is methane associated with water; the water and methane molecules are entangled in a weird fashion, but it's solid and stable under conditions that are not quite exotic.
  • Firstly, *every* place is environmentally sensitive.
    Sensitivity to strategic perturbation is one of the
    definitive aspects of complex systems. The reason
    utilization of natural resources becomes controversial
    is that what *aspects* of any given environment are
    worthy of protection is a subjective value judgement.

    In this case, failing to exploit the resource will
    result in a future ecological catastrophe which
    extends far beyond the region of Vancouver Island:
    Methane is a primary greenhouse gas. It is crucially
    important that we should extract the bulk of the
    undersea methane deposits (which extend to many,
    many other regions of the world as well) before
    the ocean temperature raises enough to vaporize
    those deposits. Otherwise, they will create a
    global warming catastrophe.

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