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Hot Water, Hot Earth
Calopteryx notes a New Scientist article on the discovery of "supercritical" water emerging from a vent in the Atlantic Ocean at 407 deg. C (765 deg. F). One of its discoverers actually said, "It's water, but not as we know it"; it's the hottest water ever found on earth. The cause seems to be a huge bubble of magma beneath the ocean floor, 3 km below the sea surface. Meanwhile Nymz shares a journal entry on a hot spot on land: a 2-acre patch in Ventura county, in California, that has heated up to 433 deg. C (812 deg. F). Here geologists blame buried hydrocarbons burning as they get access to air through cracks in the ground. That high temperature was measured a foot below the ground surface.
Once you put water under enough pressure (think 4000 PSI), you can pump almost an infite amount of heat into it without it undergoing a phase change. Useful for all sorts things, like breaking down any organic compound into constituant atoms. So the water in the story isn't the hottest on earth, only the hottest naturally occuring.
Seriously, though, wouldn't the water just convert to steam at that point, even if it WAS under that much water?
The term "supercritical" doesn't just make a nice-sounding buzzword to toss into the article.
It literally means that you can make no meaningful distinction between the liquid and gaseous phases of the water at that pressure and temperature - You have something between the two phases with no phase-change energy transition separating them.
As an aside, humans use supercritical water all the time, in power plants. This only counts as interesting because we've never seen it occur naturally before (most likely because we don't tend to hang out a lot in places at pressures above 22MPa).
Actually there is a reason: it's "supercritical".
For it to turn to steam would require a phase change between it and the surrounding water, and a supercritical fluid by definition has no distinct phase change between the liquid and gasous phases.
You'd think that if the pressure would be high enough, a liquid would stay a liquid at any arbitrary temperature, but that's not what happens. If you have a vessel strong enough to withstand the increasing pressure, and you heat a liquid within it, that has a gasous phase above it, you first see boiling. Then, as the pressure in the gas phase rises, the boiling stops. But, if you keep heating it, an interesting thing happens: the line between liquid and gas phase disappears, and the fluid only has one phase. It is supercritical.
In this case, boiling never starts because the pressure is high to begin with.
Now, the supercritical water is much less dense than seawater (or plain water, for that matter), so it does rise, and if it cools slower than the pressure drops as it rises, yes, it might start to boil.
In Liberty, Rene
Yeah, that's how they still put out oil well fires. However, if you ever seen oil "gushing" these days, that's a huge, huge problem. That stuff only happened back pre-1950's or so when they use "spudders" to drill without significant drilling fluid. These days, using rotary drilling, such heavy "mud" is used while drilling that blow-outs should never occur, as they can obviously be ridiculously dangerous.
I, personally, can't wait for Al Gore to propose a new tax because the earth is burning its own petroleum without any heed to environmental impact. SHAAAAAAAAAAAME, SHAAAAAAAME!
J
Beer, now there's a temporary solution -- Homer Jay S.
This isn't the town that had to be condemned because the coal underground was ignited?
That would be Centralia, Pennsylvania