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Methane-Trapping Ice May Have Triggered Gulf Spill
sciencehabit writes with an excerpt from Science that begins: "Methane-trapping ice of the kind that has frustrated the first attempt to contain oil gushing offshore of Louisiana may have been a root cause of the blowout that started the spill in the first place, according to [UC Berkeley] professor Robert Bea, who has extensive access to BP p.l.c. documents on the incident. If methane hydrates are eventually implicated, the US oil and gas industry would have to tread even more lightly as it pushes farther and farther offshore in search of energy."
Depth, pressure.
Nerd rage is the funniest rage.
This doesn't really answer why it's not a problem in Alaska, but the temperatures aren't actually much different. Alaskan offshore drilling is in relatively shallow water, which at those latitudes is somewhere in the low single digits C once you get below the ice pack; while this operation in the Gulf was at about 1700 meters depth, where the temperatures are also in the low single digits C. (There's lots of complicating factors, but this graph of depth v. temperature for three different latitudes gives an idea.) There's differences in pressure, which might matter, but also big differences in geology.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Is there a correlation between the amount of methane hydrates and the distance from shore?
The correlation is between distance from shore and depth + temperature.
Here's some nice graphs showing depth vs temperature for methane hydrates
And here's a picture of seafloor depths for context
[Fuck Beta]
o0t!
This one has more detail, and is actually really-well written. Really, an AP story with some investigative journalism. Kudos, guy, you're making your co-workers look bad. :)
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Oil is really valuable, so there's a very high bar for the monetary cost of disaster to be not worth it, on a purely profits-vs-cleanup-costs basis.
Some back-of-the-envelope estimates. Say this disaster ends up costing BP $10 billion. Say that any given rig has a 1% chance of causing a disaster of that magnitude. So we assign a $100 million amortized cost per rig, to cover the "chance this rig will catastrophically blow up". Is it still worth drilling in that case? Well, it actually barely changes the economics at all: these deep-water wells cost about $500-600 million to drill and put into production to begin with. So add to $100m to that and total costs are basically still on the same order of magnitude.
In particular, these rigs can produce a lot of oil. BP's Thunder Horse rig in the gulf produces 250,000 barrels per day. Even if they make only $10/barrel operating profit (probably a low estimate), that's $2.5m per day in profits from the well, i.e. almost a billion dollars per year. Unless fully 10% of such wells incur $10b catastrophic cleanup costs every year, BP comes out ahead.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
"Wacko environmentalists" have absolutely nothing to do with it. The big problem with doing that is, unfortunately, there's precious little oil left close to shore. You could fill the entire U.S. coast so full of wells it looks like a pin cushion and it would hardly make a dent in the oil price. You can see the chart right here, U.S. oil production has been on a steady decline for decades and will never, ever recover, it doesn't matter how many wells you drill. Even the discovery of the north slope of Alaska and building the pipeline never got the U.S. production to recover from its 1972 peak. ANWR? Forget about it, ANWR's a blip that's laughably too little, too late. This is why the Republican chant of "drill baby drill" is so ridiculous, drilling is pointless without oil to find. We've used up most of the oil near shore, which is why BP was drilling in 5000 feet of water, it has nothing to do with environmentalists.
Gentlemen! You can't fight in here, this is the war room!
Article says "Drillers have long been wary of methane hydrates because they can pack a powerful punch.. . . " . . . Doesn't exactly sound like this was a new and unforseen problem, . . .
The drilling is taking place in deeper and deeper water. Deep waters have high pressure and the low temperature. Both of these make formation of methane clathrates more likely. The high pressures a mile beneath the ocean surface also make it easier to dissolve gas in the oil. Avoiding pipeline blockages and explosive decompressions is not trivial. To the extent the industry is pushing the limits of what has been done before (and they are pushing limits of depth) they can be surprised by details that they haven't encountered before.
The good news is that there will be a charity concert in New Orleans, so BP won't have to pay so much money to their victims.
If it ends up like Vladez oil spill BP won't have to pay anything. More than 20 years later the fish have not recovered and the fishermen have not been compensated. Heck, oil still persists, is still found. Large corporations laugh while going to the bank to make another deposit while the people pay.
Falcon
Should there be a Law?
I wonder how they've avoided the problems up around Alaska or other places where it's actually cold enough for there to be ice - much less methane trapping ice.
I'm a gas field operator in Alberta, and hydrates can be a massive problem, especially when the wells are not big enough to justify dehydrating the gas at the well site and has to flow to a central facility. Since I operate a sour gas field (contains hydrogen sulfide) the problem is even worse. At our normal field pressures the gas starts to hydrate at around 20 C (68 F) if we are not taking extra steps to control it. It is one of the biggest causes of equipment damage and injuries/deaths. I have never operated oil wells so I am not knowledgeable about how they effect production of oil, but I have read about deaths due to mishandling hydrates at the wellhead of oil wells in Alberta and BC. To reduce the rate that they form, we inject chemicals such as methanol into the gas, and have line heaters at regular intervals along the pipeline. They are a regular problem and danger.