Deepwater Horizon well could become unchecked gusher

[ThePythonicCow]

Re: Deepwater Horizon well could become unchecked gusher

interesting, so the service boat is really the command center and not the rig?

The service boat would be the command center for the tethered remotes that were tethered to it, yes. That doesn't mean that the service boat is "the command center" for what's on the rig.

[GRG55]

Re: Deepwater Horizon well could become unchecked gusher

The problem is not as simple as that. If a moratorium on drilling happens, the supply of oil is going to shrink rapidly. So think not $3 per gal, but rather $30 per gal. How then does that impact your life style? Is the North American public willing to make the necessary changes over the next two decades? Possibly Alt-E will come through. But what happens if the technological solutions are not as feasible as currently thought?...

The Gulf of Mexico currently supplies roughly 10% of the USA domestic consumption of crude oil and also roughly 10% of the nation's natural gas supply. If there is an extended moratorium on drilling in the Gulf of Mexico as a result of this tragedy the first impact will be on natural gas production, as the decline rates of the offshore natural gas wells are quite a bit higher than for crude oil, and the current 6.7 billion cubic feet per day coming from the GoM will fall off rapidly.

[Rajiv]

Re: Deepwater Horizon well could become unchecked gusher

GRG

I was not even thinking of the production declines, but rather only of new production not coming on line. That also plays a big role in determining the rate at which total world oil and gas production declines on the down side of the peak oil curve.

If US puts a moratorium on new off shore drilling, my thought is that this will be followed by moratoriums in other deep water offshore drilling. US still remains a thought leader, and its lead is likely to be followed. I do not think that there will be a moratorium on shallow water offshore drilling, though there will be one until the causes of this accident are discovered and rectified. Already California seems to have jumped off the offshore drilling band wagon.

Schwarzenegger ends support for offshore drilling

Gov. Arnold Schwarzenegger says he will find another way to help close the state's $20 billion budget deficit after the massive oil spill in the Gulf of Mexico caused him to withdraw his support for a plan to expand oil drilling off the California coast.

Schwarzenegger announced his decision on the plan Monday, saying TV images of the spill made him change his mind about the safety of ocean-based oil platforms.

"You turn on the television and see this enormous disaster, you say to yourself, 'Why would we want to take on that kind of risk?'" he said at a news conference near Sacramento.

The Republican governor had proposed expanding oil drilling off the coast of Santa Barbara County to help plug the state's budget deficit. Democrats last year blocked a similar proposal, but Schwarzenegger renewed his support, saying it was a reliable way to increase revenue as the state grapples with an ongoing fiscal crisis.

A drilling deal struck in 2008 between some environmental groups and Plains Exploration & Production Co., known as PXP, was estimated to bring the state some $100 million a year. The governor's budget had set aside that money to keep state parks open in the next fiscal year.

On Monday, Schwarzenegger said he would come up with another way to fill the deficit.

"If I have a choice to make up $100 million and what I see in Gulf of Mexico, I'd rather find a way to make up that $100 million," he said.

The announcement assures that no new drilling will take place off the state's coastline in the foreseeable future because Schwarzenegger would have to include the drilling proposal in his May revision of the state budget.

[Roughneck]

Re: Deepwater Horizon well could become unchecked gusher

http://blog.iongeo.com/?p=1961

[ggirod]

Re: Deepwater Horizon well could become unchecked gusher

History seems to show that events like this are not all that rare. If it's not one thing, it's another. I wonder if it is feasible based on historical data to put statistical confidence intervals on oil supply estimates so people can deal with the likely consequences in a productive way.

In other words, we have people saying - it's still only $3 a gallon, so why worry, vs. other people pointing out the dire consequences of even fairly small shortfalls. The truth is somewhere between $3 and $30 but probably more like $3-$5.

I think oil price projection ranges based on the incidence of supply problems would be very useful in educating the public what to expect. If the 2 standard deviation price range is $2.50 - $6.00 that gives people a lot better picture of what to expect and a much better way to plan. Since demand is pretty well correlated to GDP, then adjusting the range as the world's economies wake up from their fitful sleep would be even better. People need to know that oil will be volatile and that it will tighten up and that they need to plan for their future.

Now, all people get told is how wonderful the latest find is, when in fact it constitutes another week of oil at world consumption rates, and that in fact more wells declined than were made up by that wonderful find. Maybe a bit of truth would help people navigate between plenty of oil and Mad Max.

[strittmatter]

Re: Deepwater Horizon well could become unchecked gusher

The caller mentions that they finished cementing the liner, which is consistent with the information I have. He also mentions they placed a seal assembly, but the video clearly shows a gas flare blowing under the helideck, which I am sure must have been coming from the diverter, which means the annulus was open. Finally, with the liner cemented there should be no way for formation fluids to enter the wellbore unless either the cement job was botched, or something on the liner [like a lap] failed [or something even more bizarre that I can't even picture happened downhole]. The post mortem on this one is going to be interesting to say the least...

http://www.northeastshooters.com/vbu...r-Horizon-Info
Deepwater Horizon Info
This is from a friend....
> Terry xxxxxxx, who works for ADTI, had a son who was one of the BP Company
> reps on the Horizon when the incident occurred. Here's what he sent me.
>
> TALKED TO MY SON, HE IS AT HOME NOW, AND IN GOOD SHAPE, WHAT I WAS TOLD WAS
> THEY HAD SET A 9-5/8 TAPERED PRODUCTION LINER, DID THEIR CEMENT JOB, HAD
> POSITIVE TESTED, AND ALSO NEGITIVE TESTED, THEY WERE GOING TO SET A BALANCED
> PLUG AROUND 3000' BELOW THE WELL HEAD WHICH WOULD BE AT ABOUT 8000', THE
> SENIOR COMPANY MAN WANTED TO SET THE BALANCED PLUG IN MUD, BUT THE ENGINEERS
> WANTED TO DISPLACE WITH WATER PRIOR TO SETTING BALANCED PLUG, SO THEY
> DISPLACED FROM 3000' BELOW MUD LINE, AND WERE GETTING READY TO SET PLUG. THE
> DERRICKMAN CALLED THE DRILLER AND SAID HE NEEDED HELP, HE HAD MUD GOING
> EVERYWHERE, AND ABOUT THIS TIME THE DRILL FLOOR DISAPEARED, THEN THERE WAS
> AN EXPLOSION, THEN A SECOND EXPLOSION.
>
> THE FLAMES ARE NOW GOING STRAIGHT UP ALLOWING EVACUATION OF MEN, THEN YOU
> KNOW THE REST.
>
> THE HANDS THAT ARE MISSING ARE THE ONES THAT WERE ON THE DRILL FLOOR AND
> PUMP ROOM. YOU KNOW THE RESULTS OF THAT. THIS ALL TOOK PLACE IN LESS THAN A
> MINUTE.
>
> RIG WAS EVACUATED IN ABOUT 25 MINUTES.
>
> IT IS BELIVED THAT THE SEAL ASSEMBLY AT THE WELL HEAD GAVE UP. IF THAT IS
> THE CASE AND THEY WOULD HAVE SET THE BALANCED PLUG IN MUD THEN DISPLACED THE
> RISER, IT WOULD ONLY HAVE DELAYED WHAT HAPPENED BY A COUPLE OF HOURS.
>
> GAS MUST HAVE CHANNELLED THROUGH THE CEMENT JOB AND UP THE BACK SIDE OF THE
> 9-5/8 PRODUCTION CASING.
>
> THIS IS ALL I KNOW AT PRESENT.

http://www.halliburton.com/public/ne...ws_043010.html

HOUSTON - Halliburton (NYSE: HAL) confirmed today its continued support of, and cooperation with, the ongoing investigations into the Deepwater Horizon drilling rig incident in the Gulf of Mexico earlier this month. Halliburton extends its heartfelt sympathy to the families, friends and our industry colleagues of the 11 people lost and those injured in the tragedy.

As one of several service providers on the rig, Halliburton can confirm the following:

• Halliburton performed a variety of services on the rig, including cementing, and had four employees stationed on the rig at the time of the accident. Halliburton's employees returned to shore safely, due, in part, to the brave rescue efforts by the U.S. Coast Guard and other organizations.
• Halliburton had completed the cementing of the final production casing string in accordance with the well design approximately 20 hours prior to the incident. The cement slurry design was consistent with that utilized in other similar applications.
• In accordance with accepted industry practice approved by our customers, tests demonstrating the integrity of the production casing string were completed.
• At the time of the incident, well operations had not yet reached the point requiring the placement of the final cement plug which would enable the planned temporary abandonment of the well, consistent with normal oilfield practice.
• We are assisting with planning and engineering support for a wide range of options designed to secure the well, including a potential relief well.

Halliburton continues to assist in efforts to identify the factors that may have lead up to the disaster, but it is premature and irresponsible to speculate on any specific causal issues.

20 hours WOC (waiting on cement) seems awfully short to me, even for a "quick-set" mix. I'd love to hear what the mud loggers have to say.

[flintlock]

Re: Deepwater Horizon well could become unchecked gusher

A buddy called me today who owns a home on the Alabama coast. This event should do wonders for an already hurting RE market down there. He will potentially be losing out on tens of thousands in rental income for just the upcoming prime vacation season. This comes on top of two hurricanes. Makes me glad I didn't buy that lot he tried to sell me several years ago.

[ThePythonicCow]

Re: Deepwater Horizon well could become unchecked gusher

http://www.halliburton.com/public/ne...ws_043010.html



20 hours WOC (waiting on cement) seems awfully short to me, even for a "quick-set" mix. I'd love to hear what the mud loggers have to say.

When Haliburton "had completed the cementing", does mean the cement was in, but not yet set, or that it was in and and set to sufficient strength to be used.

[GRG55]

Re: Deepwater Horizon well could become unchecked gusher

http://www.halliburton.com/public/ne...ws_043010.html



20 hours WOC (waiting on cement) seems awfully short to me, even for a "quick-set" mix. I'd love to hear what the mud loggers have to say.

When Haliburton "had completed the cementing", does mean the cement was in, but not yet set, or that it was in and and set to sufficient strength to be used.

"Completed the cementing" means that the operations to run the production liner and place the cement were completed. The well isn't actually put into "use" until it is completed and put on production, which is months away.

Answering strittmatter's comment...20 hours is typical, there's nothing unusual about that aspect in this well. It's almost certain that cement samples were taken at regular intervals during the cementing operation, to be used for compressive strength tests. A failed compressive strength test is rare, but it has happened [which is why samples are taken and tested]. However, the samples were probably lost with the rig, and it's unclear whether any of the tests were taken or reported given the short interval between the cementing operation and the blow out [that sort of data would be typical in the daily drilling report]. A problem with the cement composition itself is possible, but not very high probability. The positive and negative pressure tests on the installed liner were successful according to the reports.

Having said that, cementing operations in the Gulf of Mexico are notoriously difficult. The reason for this is because the reservoir pressures tend to be very close to the minimum stress for the rock. If the cement density [or drilling mud density during drilling operations] is too high it risks exceeding the fracture pressure of the rock and major fluid losses due to the breakdown of the formation. Because of this issue, it is not uncommon for operators in the Gulf of Mexico to use elastomeric seals at the liner hanger.

I speculated in one of my earliest posts on this incident that perhaps the liner lap failed. The problem with using a seal at the liner hanger is that the liner lap no longer depends entirely on the cement behind it for a pressure seal...and as far as I know there is no way to tell from the pressure tests whether there is cement to the top of the liner. There is no doubt that something downhole in the well failed which is what started the sequence of events. If this well had a seal at the liner hanger it may have failed after the pressure test if they left the well in an underbalanced condition at the end of the test.

What exactly are you implying by the "mudlogger" comment?

Edit added: It is possible that it may never be definitively determined what happened downhole. If the continuing efforts to actuate the BOPs is unsuccessful [at this time the remotes are being used to try to bypass the subsurface control systems and intervene directly on the stack itself] and the well is eventually killed by cementing it off through one of the relief wells, then whatever happened down there may be sealed up forever...

[ThePythonicCow]

Re: Deepwater Horizon well could become unchecked gusher

"Completed the cementing" means that the operations to run the production liner and place the cement were completed. The well isn't actually put into "use" until it is completed and put on production, which is months away.

I used the wrong words, so my question was misunderstood.

Does "the operations to ... place the cement were completed" mean that the concrete had set to most of its final strength, or not?

By "in use", I was not referring to "using the well to get oil". I was referring to using that just placed concrete to sustain whatever load it should have been able to sustain, once mostly set.

I am having a little trouble expressing this clearly for two reasons. For one thing, I know about 0.001% as much about this as do yourself, GRG55. And for another thing, it is my understanding that concrete can take months or years to set to maximum strength, but reaches adequate strength to hold it's design load in perhaps a few hours or days for simple work at ground level (I've no idea how that changes a mile under the ocean surface.)

The implication of an earlier post to which I was responding was that they had just poured the concrete a day before the well blew, so perhaps someone relied on the strength of that just poured concrete way too soon. I was figuring (hoping?) it would take a more complicated mistake or a more dastardly curve ball from Mother Nature than simply relying on the strength of just poured concrete to explain this blow-out.

[GRG55]

Re: Deepwater Horizon well could become unchecked gusher

Sorry for misunderstanding your original query TPC.

Hopefully my previous post provided at least a partial answer to your question.

To clarify, Halliburton provides cementing services and it would consider and report the cementing operation completed as soon as all the cement was in place. Halliburton personnel and equipment would stand down at that point.

The rig crew, on the other hand, would not consider the liner installation operation [of which the cementing operation is but one part] completed until the postiive and negative pressure tests on the liner were completed successfully. At this point, there is no indication that the wait time from placing the cement to conducting the pressure tests was unusual for this well compared to norms for such operations in the Gulf of Mexico [that doesn't meant that the norms may not need some scrutiny, however]. These tests are conducted by alternately raising the pressure in the wellbore to something higher than the formation pressures and monitoring for any pressure or fluid column losses then reducing the pressure in the wellbore to below the formation pressure and monitoring for any inflow. The way the pressure is reduced is by replacing part of the drilling mud column with seawater, which is less dense. That is part of the reason the 5000 ft riser was circulated to seawater. I don't have the actual data of course, but a quick back of the envelope calc suggests that displacing 5000 vertical ft of column to seawater would have reduced the gradient by perhaps 1100 psi. Although Halliburton wouldn't have any direct responsibility for conducting the pressure tests it likely had someone observing because a failure of either test would mean remedial cementing operations would have to be initiated.

This is likely one of the reasons the rig crew were surprised...having earlier passed the pressure tests the well should have been completely isolated from all the formations...there should have been no path for hydrocarbons to enter the wellbore from any of the potential producing horizons. Although there has been much focus in the media about the effects of the spill and the failure of the blowout preventers, as I keep repeating...the sequence of events had to have started with something failing in the well.

btw, I have been trying to write my posts so that they can be understood by any iTulper, but if I fall short people shouldn't hesitate to point that out, as you have. It's not that difficult for me to fall into the habit of using industry jargon and acronyms.

[thriftyandboringinohio]

Re: Deepwater Horizon well could become unchecked gusher

I used the wrong words, so my question was misunderstood.

Does "the operations to ... place the cement were completed" mean that the concrete had set to most of its final strength, or not?

By "in use", I was not referring to "using the well to get oil". I was referring to using that just placed concrete to sustain whatever load it should have been able to sustain, once mostly set.

I am having a little trouble expressing this clearly for two reasons. For one thing, I know about 0.001% as much about this as do yourself, GRG55. And for another thing, it is my understanding that concrete can take months or years to set to maximum strength, but reaches adequate strength to hold it's design load in perhaps a few hours or days for simple work at ground level (I've no idea how that changes a mile under the ocean surface.)

The implication of an earlier post to which I was responding was that they had just poured the concrete a day before the well blew, so perhaps someone relied on the strength of that just poured concrete way too soon. I was figuring (hoping?) it would take a more complicated mistake or a more dastardly curve ball from Mother Nature than simply relying on the strength of just poured concrete to explain this blow-out.

I spent a few minutes looking up oil well cement and, Holy Cow! (pun intended) this is high technology. Attached is a scholarly paper titled "Mud removal and cement placement during primary cementing of an oil well, Part 2; steady-state displacements", from the Journal of Engineering Mathematics.

Understanding the root cause of this accident will take huge effort, a long time, and may never give clear answers; all the evidence has been literally blown to smithereens and then the charred remains literally sunk to the bottom of the deep blue sea. Plus the materials and techniques involved are among the most advanced in the world, full of subtle complexity.

We all want clear and easy answers and a bad guy in a black hat to hang from a tree (especially if that could be Halliburton, once again discovered near the scene of a tragedy and deeply involved). This situation may not give that satisfying closure.

[strittmatter]

Re: Deepwater Horizon well could become unchecked gusher

...and as far as I know there is no way to tell from the pressure tests whether there is cement to the top of the liner.

Is it even possible to run a bonding log at that stage?

What exactly are you implying by the "mudlogger" comment?

I was thinking in terms of whether or not the mud guys were still there to monitor the returns for hydrocarbon presence when they displaced the riser. For that to be effective, I suppose they would need to displace via reverse circulation so as to expose the bottom fluid first.

In a complicated environment/operation such as this, I can see that it comes down to a "best educated guess" decision on what exact cement slurry composition to run then hope it will hold up against the known volatile physical properties of the formation.

A whole lot of these unknowns and edge of the envelope variables, as you've alluded to earlier, are reasons for the extent of redundant safety systems, checks and re checks. Since the BOP is in reality a backup mechanism, my overlying implication here stems from the notion that the best way to avoid a disaster like this is to try like heck to avoid it from happening in the first place. Much easier said than done of course.

[GRG55]

Re: Deepwater Horizon well could become unchecked gusher

I spent a few minutes looking up oil well cement and, Holy Cow! (pun intended) this is high technology. Attached is a scholarly paper titled "Mud removal and cement placement during primary cementing of an oil well, Part 2; steady-state displacements", from the Journal of Engineering Mathematics.

Understanding the root cause of this accident will take huge effort, a long time, and may never give clear answers; all the evidence has been literally blown to smithereens and then the charred remains literally sunk to the bottom of the deep blue sea. Plus the materials and techniques involved are among the most advanced in the world, full of subtle complexity.

We all want clear and easy answers and a bad guy in a black hat to hang from a tree (especially if that could be Halliburton, once again discovered near the scene of a tragedy and deeply involved). This situation may not give that satisfying closure.

Contrary to some public opinion, the oil and gas industry is one of the most technology intensive industries on earth...

[thriftyandboringinohio]

Re: Deepwater Horizon well could become unchecked gusher

...the best way to avoid a disaster like this is to try like heck to avoid it from happening in the first place. Much easier said than done of course....

Especially when you are trying to sell management on a belt-plus-suspenders approach that adds millions or tens of millions of dollars to the project.