This page has been archived and commenting is disabled.
Oil Pressure Stopping Short of Target ... Does that Mean the Well Integrity Test Is Failing?
The well integrity test is arguably failing, as the pressures are not
reaching the 8,000 psi minimum
target.
CBS News notes:
The
federal pointman for the BP oil spill says results are short of ideal
in the new cap but the oil will stay shut in for another 6 hours at
least.Retired Coast Guard Adm. Thad Allen said on a Friday
afternoon conference that pressure readings from the cap have not
reached the level that would show there are no other leaks in the well.He
said the test will go ahead for another 6-hour period before being
reassessed to see if BP needs to reopen the cap and let oil spill out
again.
MSNBC writes:
Allen said two possible reasons were being debated by
scientists: The
reservoir that is the source of the oil could be running lower than
expected three months into the spill. Or there could be an undiscovered
leak somewhere down in the well.
The New York Times reports:
Thad W. Allen, the retired Coast Guard admiral who
is overseeing the response to the gulf oil spill, said that while there
were indications from the test that the well was in good shape, it was
not yet possible to rule out damage that could complicate efforts to
halt the leak permanently.
“We want to be careful not to do
any harm or create a situation that could not be reversed,” he said in a
conference call with reporters Friday afternoon.
***
Admiral Allen said the test would continue in six-hour increments and
that any new data would be reviewed by scientists and engineers from the
government, BP and other companies. He said there would be “enhanced
monitoring” of the seabed, including acoustic tests that could detect
tiny bubbles of methane gas coming from the bed, which would be evidence
of damage to the well.
***
Admiral Allen said that such
a pressure buildup suggested that the well was not damaged. But he
said that the pressure level reached — about 6,700 pounds per square
inch, or more than 450 times atmospheric pressure — was below that
expected for an intact well.
One explanation for the ambiguity,
he said, is that the reservoir of oil 13,000 feet below the seabed
could have been depleted by the well as it galloped out of control for
nearly three months. But another possibility is that the well is
breached, with oil and gas escaping into the rock or, worse, into the
gulf through the sea floor.
BP states
that the pressure in the well is only rising 2 pounds per square inch
each hour.
I will post a transcript of Allen's report when it becomes available (here is an unofficial, rough transcript). In the meantime, blogger Wang - who attended the press conference by
telephone - added
details from Allen's press conference (I simply edited for clarity of
reading; I will update with corrected and expanded transcript as I
receive it):
Uncertainty about the meaning of the pressure. Could
be lower because of well integrity, or the reservoir has become
somewhat depleted and so is lower in pressure than expected.The
initial curve of pressure build up was normal but stopped short of our
target which is the concern.
Don't want to create harm or an
irreversible situation.
Was the reservoir depleted or is there an
ongoing way for the oil to leave the well bore? We do not know the
condition of the well bore. There's a good chance it could be
depletion. Checking out the well bore. Checking for leaks. We have no
indication of a seafloor breach so it could be reservoir depletion.
Additional seismic surveys are required.
This kind of formation
can maybe heal itself if we do damage it, the quickest way to reduce
pressure is opening the kill and choke line.If there is a problem we
will vent the oil.Reservoir depletion can be measured by
determining if there was an aquifer beneath the reservoir but there is
not one. If the seismic and acoustic show no sign of leakage we will
continue with the testing.NOAA boat looking for methane from the
sea floor with acoustic device. There is some concern about methane.
We want to make sure there is no methane. If we were to detect
methane we would lower the pressure by venting or ramp up Helix
Producer.We will reevaluate in 6 hours and have a series of
meetings (with the committee) everything moving forward is condition
based. We should have results in the next 6 hours. The 6 hour period
starts now.
There are actually at least four potential explanations for the low pressure
readings:
(1) There are substantial
leaks in the well;(2) There is leakage in the sands deep
under the seafloor. Oil industry professionals posting at the Oil Drum hypothesize:
What this could indicate is that there is a
possibility of crossflow at the bottom of the well. What this
means that the oil and gas that are flowing out of the reservoir into
the bottom of the well, are, under the pressure in the well, now flowing
into a higher reservoir of rock, now that they can't get out of the
well. Depending on where that re-injection flow is, this may, or may
not, suggest that the casing has lost integrity. This is a topic that
has been covered in the comments at The Oil Drum, where fdoleza -
"a petroleum engineering consultant retired from a major
multi-national oil company" - has noted:... I
believe the flow will be coming out of the bottom sand and going into
the upper sand. It would not be a leak, but it would tell them why
their pressure data ain't a classical surface buildup. And I sure hope
they're modeling temperatures and so on, because this is a very
interesting case. They don't have downhole gauges, so they'll have to
take the way the oil cools down as it sits to get a better idea of the
way things are moving down below.If there are
questions whether there is still flow in the formation or from the
original formation into surrounding rock, then it is possible that the
relief well (RW) is close enough to the original well (WW) that
putting a set of very sensitive microphones down the RW might allow
some triangulation to estimate where such a flow might be occurring.
It might make it easier that the well hasn’t been finally cased yet.
But the test has 2 days to run, and will be evaluated every 6 hours.
With time some of these questions may be answered as the test
continues. (If there is no flow anywhere, after a while all the
readings should become quite stable).(3) A
hypothesis proposed
by Roger N. Anderson - professor of marine geology and geophysics at
Columbia University - that the pressure could be rising slowly not
because of a leak, but because of some kind of blockage in the well:
"If it's rising slowly, that means the pipe's integrity's still there.
It's just getting around obstacles"or
(4) The reservoir
has been depleted more than engineers anticipated (although many experts
have said that the reservoir is much
bigger than BP has forecast; in any event, there are factors other
than size which determine pressure. For example, blowouts can reduce
pressure pretty quickly in some reservoirs)
While many oil industry experts are betting on damage to the well
bore or communication between layers of sand, Don Van Nieuwenhuise -
Director of the Professional Geoscience Programs at the University of
Houston - thinks
reservoir pressure has simply "deflated", and that 6,700 psi isn't
unexpected:
The
6,700 pound- per-square inch pressure reading logged inside the
blown-out Macondo well this morning may suggest that the well has lost
power over the almost three-month-long period it has flowed into the
Gulf of Mexico and not that the well is leaking somewhere beneath the
sea floor, a geologist who has been following the gusher said.The
reservoir could have "deflated" since it began leaking April 20,
reducing the amount of pressure it is capable of producing, said [Van
Nieuwenhuise].***
But Van Nieuwenhuise said this
morning's 6,700 pounds per square inch reading should not cause worry.
"I
don't think it's a cause for immediate concern, because it could
reflect a natural loss of oil in the reservoir," Van Nieuwenhuise said.
"It's amazing that it has held its strength for as long as it has."
***
When
they first said this, I said if they can get to 7,000 (pounds per
square inch) that would be good," Van Nieuwenhuise said. "The 8,000 to
9,000 estimate reflects its initial pressure, but since it's been
bleeding so much, I'm not surprised it's at 7,000."
Note 1:
Because pressures are still rising
(if only 2 lbs per hour), it probably means that the well
integrity test hasn't caused any new leaks so far.
Note 2: Oil
industry expert Robert Cavner
notes that seismic testing isn't
as straightforward as it sounds:
Seismic puts
sound into the sea floor, and
measures the time it takes for those sound waves to return. Different
kinds of rocks reflect sound waves at certain velocities, or speeds.
By measuring the time it takes for the sound to return from a certain
depth of rock, geo-scientists can draw maps of the subsurface. Often
you can get an idea of the fluid within the pore space of rocks by the
way it returns sound waves. They ran a baseline survey a couple of
days ago, and will compare that data to the data that they'll get today
to see if anything has changed around the well to indicate fluid
movement. But, as one of my geologist friends of mine likes to say,
reading seismic for precise conclusions is often like trying to observe
airplanes flying overhead while lying on the bottom of a swimming
pool. It's difficult to draw definite conclusions, even using high
frequency seismic, but it will be another data point.
»
- advertisements -
That is, until we are (eventually) baby fed some type of "solution" most here will be begging for. Whomever our portrayed "leader" is at that point will have increasing support... May not be Obama tho.... who knows
Strayed a bit off topic there didn't ya big fella?
I am waiting for the proposition that it maybe BP ought to go ahead pump out a few gazillion gallons to help solve the problem.
Good god why in the world would they not prepare to produce the freaking oil?
Our civilisation runs on it.
- har har har, they're saving it for themselves dude..cause you ain't in the club, your "civilization" will cease to "run" on it PDQ.
~8000 was the minimum target to leave it stopped. That's a fungible number and still under consideration, depending on what their analysis shows about depletion. They have seen no clear evidence of well bore failure yet. Pressure is still increasing slowly. If things keep going the way they have been, they'll be in a grayish area and use the data to make the call, although their bias is to err on the side of caution.
http://unixwiz.net/bp/tech-2010-07-16-pm.txt
is snakehead a lawyer?
Snakehead is not a lawyer.
"although their bias is to err on the side of caution."
um, we're still talking about BP, right?
at 2-10 psi per hour that is very slow - what Adm A did say was that the initial pressure build was text book, which is why they are somewhat encouraged
My guess is that when this episode is concluded they hook up Helix etc and wait for the relief wells, to your point err on the side of caution
It was funny how the "stopped" moment never got the kind of excitement it should have garnered.
Clearly this is being rolled out, as per plan.
Tick-tock...
ORI
http://aadivaahan.wordpress.com
There was plenty of excitement along the Gulf coast.
false hope is cruel.
So when do they unveil the test results and then roll out the nuke?
You see, DOE head is a nobel prize winner, and he said nuke is off the table. So, the key phrase to look for is . . . "a blue ribbon panel has been appointed to study . . ."
Only a "Blue Ribbon Panel" can trump a nobel wining DOE head.
Question: Should we nuke it?
Answer: No.
i thought they already told us the well is damaged:
http://stevenjohnhibbs.wordpress.com/2010/06/12/bp-official-admits-damag...
Simmons still says BP covering up MASSIVE HOLE miles away, cap test is "absurd"http://www.youtube.com/watch?v=scl2dgK_-Nw&feature=player_embedded
"the test would continue in six-hour increments and that any new data would be reviewed by scientists and engineers from the government, BP and other companies."
"Additional seismic surveys are required."
Starting to sound like a combination of management by scientific committee, and DOE science fair project. Always want one more measurement, never conclude anything definitive.
Augustus, gasmiinder or Rockford, if you point me to a transcript, I'll edit ...
I am confident you will point out inaccuracies, if any, and I will correct anything you prove is inaccurate ...
I put this up top because there has been a lof of debate about long term oil damage. link of from the times sunday:
http://www.nytimes.com/2010/07/18/science/earth/18enviro.html?_r=1&ref=global-home
G. W. - the guy I was offering to put you in touch with was Tom Curtis, the author of the article, not the subject of the article (he's long since dead).
Tom is an interesting guy and I will give you a link to a biographical article about him below. He lives on the gulf coast, he's a lib, and I am sure he has his "feet wet" in regards to this spill, possibly with a bioremediation slant (which is getting little to no mainstream press at all). I'd attempt to write a story about it but a.) you're the journalist and b.) I don't have the time.
Read this, if nothing else I think it is a damn good story: http://www.houstonpress.com/2000-01-20/news/the-man-who-knew-too-soon/
Also, if you did not give the TX Monthly from 1990 article a serious read, you are depriving yourself of another damn good story.
Here's a Mega Borg video http://www.youtube.com/watch?v=eCzhmGHQ_1c
Disclosure: I am not a lib, but I have owned a hybrid since 2006, and I have solar panels on my roof.
thanks for the links
Yes, tell me about the 70k psi shut in pressure we should be seeing according to your "source" Simmons. If the faucets closed, why don't we see 70KPSI???
GW, what is your area of specialization? A degreed engineer? I know the answer, but would love to hear how you describe youself- especially with the amount of years spent in the oilfield. (How many days have you been on a Rig???)
Based upon your avatar, it appears that the 70k psi shut in pressure has been released out your back end. Assuming that's a self portrait of course. :>)
put a link on prior thread re simmons retirement
Seismic is pretty unreliable as far as measurements go. The only thing Seismic is going to show you is if there is some sort of massive swelling or change in the surrounding strata. It would have to be a pretty big change to show up.
Seismic drift, processing etc... affect those measurements and it is far from exact. To give an example, seismic does not show small fractures and faults (sub-seismic). We run into these all the time during drilling. There may be many small sub-seismic fractures that are too small to be detected. To give another analogy, seismic gives you a picture of whats below, it's kind of fuzzy, and you don't have any exact depths. For instanct, i could tell you theres a reservoir, a shale cap, and fault down there, but I can only tell you within a best guess what the actual depths are. This is why you have a geologist checking the prog during drilling to determine if the seismic or geological model is correct. It is constantly updated as the actual formations are encountered during drilling. Sooooooo What does this mean for seismic in this case? It's only going to show some BIG changes. Thats it. If there aren't any BIG changes, nothing will show up. Even if the entire structure has shifted by so many feet, it may not show up.
Sonar is the measurement of the sea floor only (not the formations below). This is much more exact.
GW - Whats the latest on the relief well?
BT, I think you have better inside sources at Schlumberger and/or BP than I do.
If you can get any (cough ... leaked documents) more info on this regard, I'll make you famous
http://adropofrain.net/2010/05/rumor-schlumberger-exits-deep-horizon-hou...
The story is out. I heard this a couple months ago from someone. I heard again recently. I regard this intelligence as highly reliable ;)
I posted that back in May and stated that Schlumberger was the quiet company that I would want to have a chat with. The original story was posted on several sites including the Huffington post and the very next day a different story appeared saying Schlumberger took a "scheduled" flight off the Horizon. Every place the original story appeared was CHANGED! I still don't believe ANYBODY, why would you? They have lied and covered up since day one and now they are pulling even the harshes critics into their corner ever so slowly. I'm still with MATT SIMMONS 100%! He called it from the start and probably is the most credible source I have found. BP has infiltrated all their roaches on every site and most of the people that are considered the most credible are the ROACHES themselves. Just like everything else going on in America, this whole dog and pony show is nothing but a cover up to keep the sheeple spending and not in panic mode. Fact of the matter is we still have maybe felt only 25% of the total impact this spill will have on America. My guess is the soft sand sediment at the floor is absorbing the oil like a sponge. As it does the oil travels further into the sediment and will eventually find its way to the surface. This will take some time however when it finally pops its head out and says hello they will have to pony up to the truth and let it be known to all. The fact the GOV and BP is keeping other countries away from the site only backs up my statements. Bunch of lying sacks that are trying every way possible to minimize the situation and protect their corporate interests at the expense of the American People. I'm not a buyer and I'm not going to be HOODWINKED by this latest episode of the David Copperfield show, just look at the mainstream media news? Problem solved! Life is back to normal! go fishing! Tell that to the people in la that have lost their livelihood and will probably never get it back!
In order to believe Matt Simmons above all other news sources, you have to willingly ignore the fact that he is short BP. Why? You also have to willingly ignore the real depth of the Gulf of Mexico. Why? Is Wikipedia in on the lies and deception too? How bout Google Earth, them too?
http://blogs.barrons.com/stockstowatchtoday/2010/06/15/bp-simmons-still-sees-bankruptcy-massive-hole-at-the-well-bore/
http://en.wikipedia.org/wiki/Gulf_of_Mexico
Anyone found that missing drillpipe yet? It's the key to this whole thing I'm telling ya.
My guess is they have the pipe on shore somewhere and are using it to smoke their dope before they make up all these pipe dreams.
The Matt Simmons pipe dreams, right?
Yeah, I saw it too a couple of months ago (maybe) on theoildrum.com. Lately I have not seen it mentioned. Wonder if it will ever be substantiated from an official source? Seems like it would be pretty compelling evidence (if true) against the decision making of the BP co man.
You know guys the more I think about it the harder it is to believe. On these rigs the details of things like this get discussed and passed around VERY quickly (there is not a lot else to talk about and when it relates to safety it gets around instantly). If the well was continuing to kick LOTS of people would know about it. One of the key issues with the loss of control was that during the displacement operation they were taking a flow into the mud pits (that is documented from the Congressional data dump) for 40 minutes before the blowout. The fact that no one red flagged that and stopped the displacement was a major failure. If word was out on the rig that the well was kicking post cement job then someone would have been watching that carefully. Really - everyone on the rig is painfully aware of the danger of your position.
I'll tell you this - with the rumor out there we will KNOW what happened eventually. I can guarantee you that there are 11 families who WILL subpoena the SLB engineer - because if this is true the wrongful death suit 'limits' will be blown away.
Guys it sound like an oilfield rumor to me. IF true it is far beyond "pretty compelling evidence". Wells do NOT kick after cementing the long string - a continuing kick that was identified by ANYONE after the cement job would have been PROOF positive that you did not have control of the well. IF true someone needs to go to prison. The facts of this could be discovered easily - subpoena the logging engineer on location and ask him what happened. If it is true subpoena the SLB managers who sent the helicopter and ask "why the hell didn't you call the BP VP's you golf with and raise hell?" and if the answer is "I did" then ask "WHO?"
Truth is I have a very hard time believing it because it would be SO far outside the bounds of reasonable behavior. I'm still shaken by the mental image that came with reading it - that's how far beyond reason it would be.
Of course we did get descriptions of the events on the rig during the blowout that suggest poor lines of authority, poor decision making and what was described as an "inexperienced" guy evaluating the pressure tests. Those are things that don't happen with a good company man (you'd have to know some of these guys to understand how bizarre the "poor lines of authority" is - the first thing a good company man does is make DAMN sure EVERYBODY knows who is in charge). But it really is so egregious I have a hard time giving it credibility - kinda like those viral emails that get forwarded, it's the ones that are SO good they just 'must be true' that go viral without checking.........
I thought I read in the Houston Chronical in May that Schlumberger was on the rig to do a cement bond log and were told to leave by BP. I don't have time to look for it right now since I'm getting ready to leave for Yankee Stadium.
What I read in the Houston Chronical and the Oil & Gas Journal gave me the impression (though it didn't say it explicitly) that the well was kicking all afternoon and evening. The Transocean people recognised it, but the BP people didn't and overruled the Transocean people. This is why I concluded that the cause of the blowout was simple human error on the part of BP. I don't blame the cement job because bad cement jobs happen a lot without burning down the rig. I don't blame the BOP's, because they didn't attempt to close them until after the rig was on fire. You are supposed to close BOP's before the kick is even close to the surface. I blame human error because when you take a well control class, the number one thrust of the class is to recognise when he well is kicking. There were four well control events during the drilling of the well. They could have burned the rig down during any of those events if they didn't recognise the kick. I wrote a paper explaining all this and sent it to Zero Hedge a couple weeks ago, but they never printed it.
I can think of several reasons why the pressure didn't rise as high as they thought. They are just measuring the surface pressure and have to guess at the oil / water / gas ratio to determine the bottom hole pressure. This ratio cannot be measured at this time and it makes a big difference in calculating the bottom hole pressure.
The total pressure isn't the only thing they look at. There are subtle features of the pressure build-up test that can tell them if there is bleed-off or formation damage. That's why they stopped the relief well - so they didn't cause any subtle changes to the pressure.
And don't forget, they haven't drilled delineation wells yet. They don't even know the size of the reservoir. It might not even be big enough to be economic. (though I doubt it)
CEO, your (thoughtful) piece was printed: http://www.zerohedge.com/article/guest-post-macondo-history-blowout
The fact of the Schlumberger team being present on the rig but leaving without conducting cement bond log (at BP's request) is also documented:
http://energycommerce.house.gov/documents/20100614/Schlumberger.MC.252.Timeline.pdf
These, and other interesting tidbits are at Waxman's site: http://energycommerce.house.gov/index.php?option=com_content&view=article&id=2043:chairmen-send-letter-to-bp-ceo-prior-to-hearing&catid=122:media-advisories&Itemid=55
I still have a very hard time believing that anyone recognized that the well was kicking post-cement job and then allowed displacement to seawater. Everyone knows their life is on the line in a blowout offshore. There is nowhere to run. (speaking as someone who has literally run for his life off a drill floor and has stood beside a BOP and screwed the loose hydraulic lines back on while mud was shooting out the top - those of course in my young, foolish and pre-scientist stage).
It's just such an incredible and clear sign that you do not have control. Wells DON'T KICK if the cement is in place. And if wells DO KICK then you KNOW you didn't get a good cement job. I know we heard there was an argument etc but I have a very hard time believing Transocean would allow the displacement if they believed kicks were occurring post cement. It was Transocean people who died and they know that is what can happen.