I've got a source, a very prominent petroleum engineer (now retired), who kindly reviewed the SPE paper Stuart found and that you reference. I'm not ready to release the details — indeed, I don't have them all yet — but the upshot of his reading about North 'Ain Dar is this — what's all the fuss about? He expressed some surprise that SPE had even bothered to publish the paper since, I assume, he found little of interest in it.
I'll be publishing on this when I have all the data & interpretations I need. However, I myself was pretty convinced by the paper, especially the graphs showing how waterlogged the field was becoming. But, then I thought to run it by some people who know what they're talking about. So, mea culpa.
I think this should serve as a general warning to people here at The Oil Drum who have been especially eager to jump to conclusions about Saudi production, or have come up with some strange interpretations of the public record (what there is of it). This strikes me as grasping at straws.
It is hard to live with uncertainty. There's a lot we don't know about Saudi production. We all want to come to a conclusion. But sometimes, we can't.
I can't comment on the expertise exhibited in these articles.
However, I do believe that it is likely that KSA will have to demonstrate some of that reserve production capacity this summer...so I guess we will have something to discuss as a group then. Perhaps with a little more certainity, one way or another.
My take on the paper were that it had three points of interest, the first of which was that they weren't using the rigless water shut-off (WSO) more frequently (this is where they seal the bottom part of a well that goes down vertically into the partially flooded zone where the water flood has reached, so as to reduce the water make in the well).
The second was that they had not started to use MRC in North Ain Dar yet - though they have started putting in the wells, and bearing in mind that the paper was written a while ago. Interestingly they had also put in the control valves on the laterals, so that they could control extraction as the water came nearer the well horizon.
The third was that (and this was partly why I made the calculation) it seems to suggest that in 15 years the field will be over.
There were some technical points also that were interesting - vide the success rate of the WSO, and the fact that they have been using more conventional horizontal wells (of the type I just illustrated) to revive some of the "dead" wells.
I don't mean to quibble but your post says absolutely nothing about why Stuart's interpretation of the Saudi information is wrong. All you've done is cast an unspecific aspersion without any data other than an unnamed source with unnamed conclusions. In the computer world this is called "FUD" (fear, Uncertainty and Doubt) and is deeply, deeply frowned upon.
I'm sure you have interesting information on hand but please refrain from posting until you are willing to share.
I have things to do, and won't be hanging around here today. But, I said
I'll be publishing on this when I have all the data & interpretations I need.
And I will do this, so stay tuned. I'm sorry if you think my giving everyone "a taste" of what's forthcoming is inappropriate.
By the way, just who is spreading "Fear, Uncertainty and Doubt" about Saudi Arabia's oil production? It isn't me. You might examine your own confusion around this point.
Even if there is a conflict of interest, but it is open and declared, then I'll be very interested.
But I do agree that it does little good to use an anonymous source to cast doubt on Stuart's and Euan's work. It's no answer to say that Stuart et al are doing the same: they laid out their case -- whether one finds it conclusive or not is a separate issue.
"I don't mean to quibble but your post says absolutely nothing about why Stuart's interpretation of the Saudi information is wrong. All you've done is cast an unspecific aspersion without any data other than an unnamed source with unnamed conclusions."
Dave does this all the time, and what he does produce in the end tends to be questionable and biased, doesn't actually address the issue or remains ambiguous.
I guess we should just all trust the professionals in the oil industry to keep production rising and prices stable, huh? I'm sure they all know what they're doing and we'd never see any problems with our energy supply. Oh, wait...
I am looking through your "nosedive" topic to see how much net oil you are missing with the additive effects of the new projects.
I think the after breakthrough cut in Ain Dar/ Shedgum should be about 90% water... so you should be missing 1.7 MMBOPD less the new oil on the SA total curve.
Production in Ain Dar/Shedgum is now 300,000 BOPD and 2.7 MMBWPD... from 2 MMBOPD and 1 MMBWPD in 2003 if the water has risen to the top of the crest. Until someone shows me different, I find it hard to see any other way.
The above is the historical flood front velocity in North Ain Dar.. it appears to be moving at 4.6 ft/day.
This cannot be the rate of vertical movement (the field would have watered out in 250 days) .... so it must be the horizontal movement towards the crest (or approximately east and west on both sides of the North South structure).
What we seek is the vertical movement associated with this horizontal movement. This is related to the dip angle of the structure. It appears from the Greg Croft structure that the dip angle of North Ain Dar is about 3 degrees, I have a reference which says it is 5 degrees.
But 3 degrees is the most conservative, and at this angle, things happen vertically at 1/20th the rate of the horizontal, at 5 degrees, it is 1/11th .
Now, it appears that we have a cut-off date of 1/1/04, so it has been about 1185 days since the cross sections of the water level in that reservoir were effective.
At a horizontal rate of 4.6 ft/day over 1185 days, what water front has converged a distance of 5450' on both sides towards the crest of that structure.
So, the water level has moved up 237 feet since that cross section in the paper was published.
I think the Western cross shows a water level on 1/1/04 of -5,900', based on a vertical scale off of the 1940 picture with the original water oil contact.
Now if I'm correct, the current water front is -5,900 + 237 = -5,663'. If you or your friend look at the Greg Croft structure, how much of that reservoir is left water-free??
Note that through the saddles between North Ain Dar, South Ain Dar, and Shedgum, all areas spill into each other and we would expect gravity equilibration. So the water level is likely consistent between all three. Now if we have 2 MMBOPD which is going to no water free (dry oil) area, could that not result in some production problems??
Look at the wet area % contribution graph and the oil production water cut curve for North Ain Dar. Note that if you factor out the increasing dry area contribution and take into account the 100,000 BOPD loss in production for the area, the true water cut in the wet area is 65%... despite all the horizontal schmontel WSO umbrella plug BS the prior historical trend in water cut behavior continued unabated.
You went from 42% water and 90%+ wet area in late 98 at 600,000 BOPD to 42% water 65% wet area at 500 KBOPD at 1/1/04. Do the algebra, the wet area is 65% water and plot it on Figure 1 of that paper.
NC did a good translation for the mathematically challenged, confirmed by FF last time they talked about this:
NC on March 27, 2007 - 11:10pm | Permalink | Subthread
Fractional_Flow,
Wonderful set of information you have been posting the last few days. I have been struggling to keep up with the math posted. At the risk of sounding very stupid on this forum I will try and paint a picture of what I understand is happening in Gharwar. Helps me consolodate information and maybe it will help others.
I think 3-dimensionally and it seemed obvious to me after your's and Stuart's posts that what has happenning in Gharwar is that the water was "crowding" the oil into the top of the reservoir. The shape is a very gentle curved, elogated dome, think of just the top surface (with a bit of down curving sides) of a very large diameter pipe lying on the ground. The side go down a distance say 10-20 times the thickness of the wall. With this model only the thickness of the pipe wall contains oil.
The thickness of this wall (oil) region is very thin from outside to inside, but very thick when viewed in tangential section where a horizontal straight line would enter from the outside pass just above the inner surface and pass out the opposite side. By using water injection oil in the pipewall below this horizontal line can be "crowded" upwards from both sides where it is removed at the top.
By using horizontal wells placed at very strategic locations along the long axis of the pipe shaped field oil a constant flow of oil output can be maintained as long as the pressure is maintained and the water is below the level of the horizontal well. The Saudis can maintain essentially constant BPD from the field by capturing almost all the oil dispaced upwards by the water.
There will be mixing of oil and water near the contact point but if the rock is porous enough (and the water is injected at the bottom) most of this mixing will initially be well below the horizontal wells. Very little water/oil mixing will occur at the horizontal wells because they are reltively far away from the water front, hundreds of vertical feet and also "around the bend" of the curved wall.
All is fine until the water layer gets up into the flat, top part, of the imaginary pipe wall. At that point the water can race across the wide flat part of the pipe wall (top of the reservoir) and mix with the oil column which may be miles wide but only a few hundred feet thick. Again the Saudi's can work around this a bit by finding the high spots (after all it is not a smooth surface like our pipe wall) above the general top of the reservoir and lay in a bunch of horizontals to maintain extraction rates.
In this manner the oil is continually pushed (for decades) from the lowest part of the reservoir to the top with very little water mixed in at the well location. A very constant, high rate of extraction can be maintained that is all out of proportion to the amount of oil remaining compared to most reservoirs. This is due to the combination of horizontal wells, porosity and the unique shape of the reservoir.
The problem comes when the water finally gets to those last series of top level horizontal wells. By the time you get significant water mixed with the oil, the water % is going to increase very quickly. In my simplistic model and understanding there isn't really much oil left. It's all water below the mixed zone and that mix zone is now restricted to the very top of the reservoir.
If my overly simplistic model is even close to accurate you can't pump water in for another 30 years and get significant oil out like in Texas. All you are going to get is water, because the oil was washed out of the lower rock strata years ago.
All comments, clarifications and even hoots of derision (at my lack of understanding) are welcomed because Id like to be completely wrong so I can sleep at night.
Parent | Parent subthread | Reply | Start new thread
Fractional_Flow on March 28, 2007 - 7:39am | Permalink | Subthread
No your physical description is just about right.
The high rate of extraction up until the last possible moment is quite a reality of this type of geometry (I believe West Texas has shared some such experience).
We need someone with advanced imaged analysis capabilities to tell us everything there is to extract from the Ain Dar cross sections in that SPE paper.
Tell your retired petroleum engineer that the impact of that paper is that if what I did above is correct or close to correct .... then 2 MMBOPD-- is essentially gone.
And I didn't correct it for contracting geometry- Stuart (and others) will know what I mean.
But I am looking for an error somewhere- it just cannot be.
"But I am looking for an error somewhere- it just cannot be."
Oh, yes it can. More important(as if this isn't bad enough news), how many other fields have used the same technology for how long? How many others are on the verge of collapse?
This brings to mind another question; What if world crude oil production were down to 50 mb/d by 2010? What if we discovered we have just stepped off the cliff and are currently in in the freefall of a World Crude Oil Production Crash?
Cid,
This is extreemly sobering.
I'm reasonably certain that I followed how FF came to the conclusions he has. This only makes it worse. I read this mid-day and it literally sent a chill down my spine. I reread it tonight and I find that I didn't get my understanding wrong. I guess we really should be have been expecting this kind of post at some point from someone very knowledgeable, pragmatic, detailed, and willing to get the word out. I do notice a lack of credible or for that matter uncredible rebuttals to FF, this adds greatly to my fear. You can follow along, and know he is right. It has that ring of truth to it and it makes sense, friggin' deeply disturbing and unfortunate sense. I have been following this for over a year now, I think new readers are going to get a bigger shock to this kind of post. This is not good stuff.
FF's post would make sense and explain KSA's coolness toward the Bush Admin., that the US is pushing KSA and KSA is saying repeatedly that there is nothing they can do and are getting tired of being pushed to do what isn't possible. We are in the end game now.
Bush and Cheney cannot be ignorant or stupid on the topic of PO. Thier idea of handling this with the Iraq invasion will probably be looked back historically as the last nails in the coffin. I wonder if they had a chance for painful mitigation given the euphoric state of current lifestyles. I don't see people willingly powering down, and that is what's required. The people won't vote for it, and you won't get campaign contributions if ELP is your platform. Maybe later but not now and not for the last 30 years.
We live in temporary, unsustainable, high technological times, yet we haven't physically evolved into anything superior to what our most recient ancestors were. We are more advanced, better educated, have a greater understanding of many things but are still the same as they were. It's too bad I liked the startrek/starwars idea of some day long distance space travel. I see that it will never ever happen and I think that is very sad but also very fortunate for the rest of our solar system.
There was an article in Natl' Geo. about Disney in florida and how horrible the sprawl is down there. They had a comment from a dade co. commisioner "Just because we have destroyed 90% of everything doen't mean that we can't do something wonderful with the remaining 10%". We have trashed our planet. You hear people talk of limited nuclear war as if this is a solution to something. They want to mark nuclear waste sites with some sort of warning that will be able to be understood 25,000 years from now. This is the very best we are able to do collectively as a species - it doesn't really say much. "Here is the posionous leftovers from our "advanced" civilization" Oh BTW sorry we fucked up the place.
Watching how people work in groups makes the whole PO problem so very understandable. How our politicians are elected and the special interest money needed to run a campaign and the favors owed to people and companies that do not have the well being of the greater population at heart. and for what? Money for more plastic crap we don't need? More security? A way to look down thier noses at others? We are still so very primitive...
HO and FF - a heart felt thank you! Looks like we had better get prepared, this can only get tough, and alot sooner than I had hoped for.
You hear people talk of limited nuclear war as if this is a solution to something.
Thats me I assure I don't agree with the concept. But in playing devils advocate to explore the position I did not see that it was unreasonable for people to take this option.
I certainly don't agree with it in any shape or form.
re: "...playing devil's advocate...I did not see it was unreasonable..."
I had an exchange (began w. my reply to bunyon) w. Cid, which may also apply to what you say here. If you get a chance to read it, I'd appreciate it. http://www.theoildrum.com/node/2375#comment-169763. (and if you could also read down to my next reply. Thanks.)
Darn. I just wrote a response and lost it all and don't have time to re-do it.
Bottom line? You can't reason with this type of testosterone driven male thinking because it has NOTHING to do with reason. It IS a "failure of imagination and heart" as you so eloquently put it, but you will never be able to make them see that side. In simpler terms, it's that Alpha Male Syndrome and it dooms mankind (like the Chimp said). When was the last time we elected a nerd? As far as I can tell, every male politician is an Alpha Male. Our leaders are Alpha Males to the extreme and the solutions they choose will undoubtedly be very bad.
Cheryl
There is something to the idea that people approach things differently, and men and women often seem to.
In my post, I intended to discuss the ideas of reason and logic in relation to the argument (I mean "argument" in the sense of rhetoric - or a justification.)
I may not have said it as well as I could have. There's an inherent problem with the argument itself. (IMHO). Though it's quite good to take a look from "inside" what appears to be an unreasonable stance, in order to understand it, my
point was simply that the logic doesn't hold, as far as I can see. There's a kind of insularity to it.
It's difficult to talk about things like this, especially when we have a format where we tend to drop things after a day or two and it's hard to "finish" a conversation.
I was asking (and would still be interested) to see if the argument I presented was at least laid out well. Did Cid agree it represented his view?
Would memmel agree it is a fair re-statement of what he was looking at as "Devil's Advocate"? In other words, does the argument, just to begin with...represent the "Devil's" position, as memmel sees it?
I'm a little confused about whether memmel is/was referring to:
1) using nuclear weapons (and we may as well include conventional weapons) as "trade items" or
2) about the idea of reducing the population (or some part of it) in this way.
3) (Or both.)
In terms of the trade concept, Chalmers Johnson has written at length about this, as have others. If I may quote Johnson from memory "The US is the only empire in the history of the world to arm its colonies."
I believe memmel had another reply to his concern as well.
On the practical side, I wanted to encourage people to get in touch with some of the people who now work (actively) to prevent nuclear war. This might be a good "peak oil outreach" action item, if one is interested in some positive "networking". (www.idds.org, www.fas.org, www.cdi.org).
Memmel, I understand. There are those who view this an an option. After 9/11 there was some lady being interviewed on her way to work that wanted to use "small" nuclear weapons to get Ossama. "one or two" - " we have some don't we? small ones?" ( if I remember correctly this was the jist of what she said)
I think because of Japan and WWII there is a sense of limited use and survivability in many folks minds. I just think it would get completely out of hand.
By all means, throw in a little "X" chromosome for a slightly gentler touch and let's make it just "one or two, we have some don't we, SMALL ones?" as opposed to the Alpha Males who would choose to "juse a BIG one and just wipe them all off the face of the planet forever. Problem SOLVED." I can pretty much guarantee that the woman didn't come up with this on her own--she has been listening to the men around her, but she softened it with "small ones," which is what she has--no "female cajones" of her own (and trust me, they do exist).
No matter how advanced "civilization" becomes, humans seem unable to control, or even comprehend, their limbic instincts, which is why I'm not optimistic about the future.
"I'm reasonably certain that I followed how FF came to the conclusions he has. This only makes it worse. I read this mid-day and it literally sent a chill down my spine."
It is interesting that as we followed it, we were able to see the conclusion it was leading to well before FF was willing to state it. That just shows he tried very hard to prove himself wrong and still didn't want to say it when he could find no where else to go.
Yes, and it makes it all the more sobering. You can understand and see that he doesn't like his conclusions and would welcome someone to point out some error. I would like that as well. I just don't see it happening. Deep down you know that oil is finite and other places around the world are in undeniable decline so we are just getting another one. So, I sit here at my dinning room table wanting...what? The truth? I think I have it. The implications of PO are so staggering. I don't know what I feel, dread, remorse, defeat, foresight, understanding, motivation? People are going to be numbed by the multi-front way this hits.
Yep, there she goes! Cantarell slips under the waves.
Cantarell´s daily production in February was 1.567 million barrels, an 18 percent drop from 1.912 million barrels in February 2006 and a 1.5 percent slide from 1.591 million barrels in January, according to the Energy Secretariat´s web site.
Hi, HO. Here's hoping you're doing well.
I've got a source, a very prominent petroleum engineer (now retired), who kindly reviewed the SPE paper Stuart found and that you reference. I'm not ready to release the details — indeed, I don't have them all yet — but the upshot of his reading about North 'Ain Dar is this — what's all the fuss about? He expressed some surprise that SPE had even bothered to publish the paper since, I assume, he found little of interest in it.
I'll be publishing on this when I have all the data & interpretations I need. However, I myself was pretty convinced by the paper, especially the graphs showing how waterlogged the field was becoming. But, then I thought to run it by some people who know what they're talking about. So, mea culpa.
I think this should serve as a general warning to people here at The Oil Drum who have been especially eager to jump to conclusions about Saudi production, or have come up with some strange interpretations of the public record (what there is of it). This strikes me as grasping at straws.
It is hard to live with uncertainty. There's a lot we don't know about Saudi production. We all want to come to a conclusion. But sometimes, we can't.
best,
Dave
I can't comment on the expertise exhibited in these articles.
However, I do believe that it is likely that KSA will have to demonstrate some of that reserve production capacity this summer...so I guess we will have something to discuss as a group then. Perhaps with a little more certainity, one way or another.
Hi, Dave, glad to see you here!
My take on the paper were that it had three points of interest, the first of which was that they weren't using the rigless water shut-off (WSO) more frequently (this is where they seal the bottom part of a well that goes down vertically into the partially flooded zone where the water flood has reached, so as to reduce the water make in the well).
The second was that they had not started to use MRC in North Ain Dar yet - though they have started putting in the wells, and bearing in mind that the paper was written a while ago. Interestingly they had also put in the control valves on the laterals, so that they could control extraction as the water came nearer the well horizon.
The third was that (and this was partly why I made the calculation) it seems to suggest that in 15 years the field will be over.
There were some technical points also that were interesting - vide the success rate of the WSO, and the fact that they have been using more conventional horizontal wells (of the type I just illustrated) to revive some of the "dead" wells.
Dave,
I don't mean to quibble but your post says absolutely nothing about why Stuart's interpretation of the Saudi information is wrong. All you've done is cast an unspecific aspersion without any data other than an unnamed source with unnamed conclusions. In the computer world this is called "FUD" (fear, Uncertainty and Doubt) and is deeply, deeply frowned upon.
I'm sure you have interesting information on hand but please refrain from posting until you are willing to share.
Thanks,
Gary
I have things to do, and won't be hanging around here today. But, I said
And I will do this, so stay tuned. I'm sorry if you think my giving everyone "a taste" of what's forthcoming is inappropriate.By the way, just who is spreading "Fear, Uncertainty and Doubt" about Saudi Arabia's oil production? It isn't me. You might examine your own confusion around this point.
Dave: if you can get experienced people with no conflict of interest to discuss the issue in detail publicly, that will be valuable.
Did you get an email about demand/supply?
Subject: Saudi Oil Production
Even if there is a conflict of interest, but it is open and declared, then I'll be very interested.
But I do agree that it does little good to use an anonymous source to cast doubt on Stuart's and Euan's work. It's no answer to say that Stuart et al are doing the same: they laid out their case -- whether one finds it conclusive or not is a separate issue.
I'll send you some mail.
"I don't mean to quibble but your post says absolutely nothing about why Stuart's interpretation of the Saudi information is wrong. All you've done is cast an unspecific aspersion without any data other than an unnamed source with unnamed conclusions."
Dave does this all the time, and what he does produce in the end tends to be questionable and biased, doesn't actually address the issue or remains ambiguous.
I guess we should just all trust the professionals in the oil industry to keep production rising and prices stable, huh? I'm sure they all know what they're doing and we'd never see any problems with our energy supply. Oh, wait...
Stuart-
I am looking through your "nosedive" topic to see how much net oil you are missing with the additive effects of the new projects.
I think the after breakthrough cut in Ain Dar/ Shedgum should be about 90% water... so you should be missing 1.7 MMBOPD less the new oil on the SA total curve.
Production in Ain Dar/Shedgum is now 300,000 BOPD and 2.7 MMBWPD... from 2 MMBOPD and 1 MMBWPD in 2003 if the water has risen to the top of the crest. Until someone shows me different, I find it hard to see any other way.
No doubt confirmed by the announced export cuts.
If it helps I did a bit of digging into oil consumption in the KSA it looks to me like the numbers could easily be low.
By about 200-500kbd.
I sent the info to WT. So if your seeing say 2GB of oil missing it could have well gone into internal consumption.
I could find nothing that would justify the low average oil consumption for KSA compared to Kuwait for example.
The US is at like 0.08mbpd per million
And Kuwait is at 0.12mbpd per million
If you plugin 0.10 per million for KSA you come up with 2.4 mbpd.
The above is the historical flood front velocity in North Ain Dar.. it appears to be moving at 4.6 ft/day.
This cannot be the rate of vertical movement (the field would have watered out in 250 days) .... so it must be the horizontal movement towards the crest (or approximately east and west on both sides of the North South structure).
What we seek is the vertical movement associated with this horizontal movement. This is related to the dip angle of the structure. It appears from the Greg Croft structure that the dip angle of North Ain Dar is about 3 degrees, I have a reference which says it is 5 degrees.
But 3 degrees is the most conservative, and at this angle, things happen vertically at 1/20th the rate of the horizontal, at 5 degrees, it is 1/11th .
Now, it appears that we have a cut-off date of 1/1/04, so it has been about 1185 days since the cross sections of the water level in that reservoir were effective.
At a horizontal rate of 4.6 ft/day over 1185 days, what water front has converged a distance of 5450' on both sides towards the crest of that structure.
So, the water level has moved up 237 feet since that cross section in the paper was published.
I think the Western cross shows a water level on 1/1/04 of -5,900', based on a vertical scale off of the 1940 picture with the original water oil contact.
Now if I'm correct, the current water front is -5,900 + 237 = -5,663'. If you or your friend look at the Greg Croft structure, how much of that reservoir is left water-free??
Note that through the saddles between North Ain Dar, South Ain Dar, and Shedgum, all areas spill into each other and we would expect gravity equilibration. So the water level is likely consistent between all three. Now if we have 2 MMBOPD which is going to no water free (dry oil) area, could that not result in some production problems??
Look at the wet area % contribution graph and the oil production water cut curve for North Ain Dar. Note that if you factor out the increasing dry area contribution and take into account the 100,000 BOPD loss in production for the area, the true water cut in the wet area is 65%... despite all the horizontal schmontel WSO umbrella plug BS the prior historical trend in water cut behavior continued unabated.
You went from 42% water and 90%+ wet area in late 98 at 600,000 BOPD to 42% water 65% wet area at 500 KBOPD at 1/1/04. Do the algebra, the wet area is 65% water and plot it on Figure 1 of that paper.
And over the course of the last 3.33 years since that paper was written, the water cut in the wet area on the same trend has risen to 80.30%.
NC did a good translation for the mathematically challenged, confirmed by FF last time they talked about this:
NC on March 27, 2007 - 11:10pm | Permalink | Subthread
Fractional_Flow,
Wonderful set of information you have been posting the last few days. I have been struggling to keep up with the math posted. At the risk of sounding very stupid on this forum I will try and paint a picture of what I understand is happening in Gharwar. Helps me consolodate information and maybe it will help others.
I think 3-dimensionally and it seemed obvious to me after your's and Stuart's posts that what has happenning in Gharwar is that the water was "crowding" the oil into the top of the reservoir. The shape is a very gentle curved, elogated dome, think of just the top surface (with a bit of down curving sides) of a very large diameter pipe lying on the ground. The side go down a distance say 10-20 times the thickness of the wall. With this model only the thickness of the pipe wall contains oil.
The thickness of this wall (oil) region is very thin from outside to inside, but very thick when viewed in tangential section where a horizontal straight line would enter from the outside pass just above the inner surface and pass out the opposite side. By using water injection oil in the pipewall below this horizontal line can be "crowded" upwards from both sides where it is removed at the top.
By using horizontal wells placed at very strategic locations along the long axis of the pipe shaped field oil a constant flow of oil output can be maintained as long as the pressure is maintained and the water is below the level of the horizontal well. The Saudis can maintain essentially constant BPD from the field by capturing almost all the oil dispaced upwards by the water.
There will be mixing of oil and water near the contact point but if the rock is porous enough (and the water is injected at the bottom) most of this mixing will initially be well below the horizontal wells. Very little water/oil mixing will occur at the horizontal wells because they are reltively far away from the water front, hundreds of vertical feet and also "around the bend" of the curved wall.
All is fine until the water layer gets up into the flat, top part, of the imaginary pipe wall. At that point the water can race across the wide flat part of the pipe wall (top of the reservoir) and mix with the oil column which may be miles wide but only a few hundred feet thick. Again the Saudi's can work around this a bit by finding the high spots (after all it is not a smooth surface like our pipe wall) above the general top of the reservoir and lay in a bunch of horizontals to maintain extraction rates.
In this manner the oil is continually pushed (for decades) from the lowest part of the reservoir to the top with very little water mixed in at the well location. A very constant, high rate of extraction can be maintained that is all out of proportion to the amount of oil remaining compared to most reservoirs. This is due to the combination of horizontal wells, porosity and the unique shape of the reservoir.
The problem comes when the water finally gets to those last series of top level horizontal wells. By the time you get significant water mixed with the oil, the water % is going to increase very quickly. In my simplistic model and understanding there isn't really much oil left. It's all water below the mixed zone and that mix zone is now restricted to the very top of the reservoir.
If my overly simplistic model is even close to accurate you can't pump water in for another 30 years and get significant oil out like in Texas. All you are going to get is water, because the oil was washed out of the lower rock strata years ago.
All comments, clarifications and even hoots of derision (at my lack of understanding) are welcomed because Id like to be completely wrong so I can sleep at night.
Parent | Parent subthread | Reply | Start new thread
Fractional_Flow on March 28, 2007 - 7:39am | Permalink | Subthread
No your physical description is just about right.
The high rate of extraction up until the last possible moment is quite a reality of this type of geometry (I believe West Texas has shared some such experience).
We need someone with advanced imaged analysis capabilities to tell us everything there is to extract from the Ain Dar cross sections in that SPE paper.
Dave-
Tell your retired petroleum engineer that the impact of that paper is that if what I did above is correct or close to correct .... then 2 MMBOPD-- is essentially gone.
And I didn't correct it for contracting geometry- Stuart (and others) will know what I mean.
But I am looking for an error somewhere- it just cannot be.
"But I am looking for an error somewhere- it just cannot be."
Oh, yes it can. More important(as if this isn't bad enough news), how many other fields have used the same technology for how long? How many others are on the verge of collapse?
Thats in a sense what I'm asking in my other posts. I think I lack a perspective on Ghawar vs other fields.
This brings to mind another question; What if world crude oil production were down to 50 mb/d by 2010? What if we discovered we have just stepped off the cliff and are currently in in the freefall of a World Crude Oil Production Crash?
Cid,
This is extreemly sobering.
I'm reasonably certain that I followed how FF came to the conclusions he has. This only makes it worse. I read this mid-day and it literally sent a chill down my spine. I reread it tonight and I find that I didn't get my understanding wrong. I guess we really should be have been expecting this kind of post at some point from someone very knowledgeable, pragmatic, detailed, and willing to get the word out. I do notice a lack of credible or for that matter uncredible rebuttals to FF, this adds greatly to my fear. You can follow along, and know he is right. It has that ring of truth to it and it makes sense, friggin' deeply disturbing and unfortunate sense. I have been following this for over a year now, I think new readers are going to get a bigger shock to this kind of post. This is not good stuff.
FF's post would make sense and explain KSA's coolness toward the Bush Admin., that the US is pushing KSA and KSA is saying repeatedly that there is nothing they can do and are getting tired of being pushed to do what isn't possible. We are in the end game now.
Bush and Cheney cannot be ignorant or stupid on the topic of PO. Thier idea of handling this with the Iraq invasion will probably be looked back historically as the last nails in the coffin. I wonder if they had a chance for painful mitigation given the euphoric state of current lifestyles. I don't see people willingly powering down, and that is what's required. The people won't vote for it, and you won't get campaign contributions if ELP is your platform. Maybe later but not now and not for the last 30 years.
We live in temporary, unsustainable, high technological times, yet we haven't physically evolved into anything superior to what our most recient ancestors were. We are more advanced, better educated, have a greater understanding of many things but are still the same as they were. It's too bad I liked the startrek/starwars idea of some day long distance space travel. I see that it will never ever happen and I think that is very sad but also very fortunate for the rest of our solar system.
There was an article in Natl' Geo. about Disney in florida and how horrible the sprawl is down there. They had a comment from a dade co. commisioner "Just because we have destroyed 90% of everything doen't mean that we can't do something wonderful with the remaining 10%". We have trashed our planet. You hear people talk of limited nuclear war as if this is a solution to something. They want to mark nuclear waste sites with some sort of warning that will be able to be understood 25,000 years from now. This is the very best we are able to do collectively as a species - it doesn't really say much. "Here is the posionous leftovers from our "advanced" civilization" Oh BTW sorry we fucked up the place.
Watching how people work in groups makes the whole PO problem so very understandable. How our politicians are elected and the special interest money needed to run a campaign and the favors owed to people and companies that do not have the well being of the greater population at heart. and for what? Money for more plastic crap we don't need? More security? A way to look down thier noses at others? We are still so very primitive...
HO and FF - a heart felt thank you! Looks like we had better get prepared, this can only get tough, and alot sooner than I had hoped for.
Best of luck to you guys.
D
Thats me I assure I don't agree with the concept. But in playing devils advocate to explore the position I did not see that it was unreasonable for people to take this option.
I certainly don't agree with it in any shape or form.
Hi m,
re: "...playing devil's advocate...I did not see it was unreasonable..."
I had an exchange (began w. my reply to bunyon) w. Cid, which may also apply to what you say here. If you get a chance to read it, I'd appreciate it. http://www.theoildrum.com/node/2375#comment-169763. (and if you could also read down to my next reply. Thanks.)
Darn. I just wrote a response and lost it all and don't have time to re-do it.
Bottom line? You can't reason with this type of testosterone driven male thinking because it has NOTHING to do with reason. It IS a "failure of imagination and heart" as you so eloquently put it, but you will never be able to make them see that side. In simpler terms, it's that Alpha Male Syndrome and it dooms mankind (like the Chimp said). When was the last time we elected a nerd? As far as I can tell, every male politician is an Alpha Male. Our leaders are Alpha Males to the extreme and the solutions they choose will undoubtedly be very bad.
Cheryl
George Bush an Alpha Male? HA HA HA HA HA HA HA HA(falling to the floor)HA HA HA HA HA HA HA HA... ROTFLMAO
How about Nancy Pelosi for Alpha Female?
Thanks, Cheryl,
There is something to the idea that people approach things differently, and men and women often seem to.
In my post, I intended to discuss the ideas of reason and logic in relation to the argument (I mean "argument" in the sense of rhetoric - or a justification.)
I may not have said it as well as I could have. There's an inherent problem with the argument itself. (IMHO). Though it's quite good to take a look from "inside" what appears to be an unreasonable stance, in order to understand it, my
point was simply that the logic doesn't hold, as far as I can see. There's a kind of insularity to it.
It's difficult to talk about things like this, especially when we have a format where we tend to drop things after a day or two and it's hard to "finish" a conversation.
I was asking (and would still be interested) to see if the argument I presented was at least laid out well. Did Cid agree it represented his view?
Would memmel agree it is a fair re-statement of what he was looking at as "Devil's Advocate"? In other words, does the argument, just to begin with...represent the "Devil's" position, as memmel sees it?
I'm a little confused about whether memmel is/was referring to:
1) using nuclear weapons (and we may as well include conventional weapons) as "trade items" or
2) about the idea of reducing the population (or some part of it) in this way.
3) (Or both.)
In terms of the trade concept, Chalmers Johnson has written at length about this, as have others. If I may quote Johnson from memory "The US is the only empire in the history of the world to arm its colonies."
I believe memmel had another reply to his concern as well.
On the practical side, I wanted to encourage people to get in touch with some of the people who now work (actively) to prevent nuclear war. This might be a good "peak oil outreach" action item, if one is interested in some positive "networking". (www.idds.org, www.fas.org, www.cdi.org).
Memmel, I understand. There are those who view this an an option. After 9/11 there was some lady being interviewed on her way to work that wanted to use "small" nuclear weapons to get Ossama. "one or two" - " we have some don't we? small ones?" ( if I remember correctly this was the jist of what she said)
I think because of Japan and WWII there is a sense of limited use and survivability in many folks minds. I just think it would get completely out of hand.
By all means, throw in a little "X" chromosome for a slightly gentler touch and let's make it just "one or two, we have some don't we, SMALL ones?" as opposed to the Alpha Males who would choose to "juse a BIG one and just wipe them all off the face of the planet forever. Problem SOLVED." I can pretty much guarantee that the woman didn't come up with this on her own--she has been listening to the men around her, but she softened it with "small ones," which is what she has--no "female cajones" of her own (and trust me, they do exist).
No matter how advanced "civilization" becomes, humans seem unable to control, or even comprehend, their limbic instincts, which is why I'm not optimistic about the future.
Has anyone seen production figures for Burgan since the 1.7 mb/d stated in Nov 2005?
"I'm reasonably certain that I followed how FF came to the conclusions he has. This only makes it worse. I read this mid-day and it literally sent a chill down my spine."
It is interesting that as we followed it, we were able to see the conclusion it was leading to well before FF was willing to state it. That just shows he tried very hard to prove himself wrong and still didn't want to say it when he could find no where else to go.
"...he tried very hard to prove himself wrong..."
Yes, and it makes it all the more sobering. You can understand and see that he doesn't like his conclusions and would welcome someone to point out some error. I would like that as well. I just don't see it happening. Deep down you know that oil is finite and other places around the world are in undeniable decline so we are just getting another one. So, I sit here at my dinning room table wanting...what? The truth? I think I have it. The implications of PO are so staggering. I don't know what I feel, dread, remorse, defeat, foresight, understanding, motivation? People are going to be numbed by the multi-front way this hits.
Petroleum Economist (can't be sure of accuracy), was quoting 1.5 Mb/d figure in Sept 2006 for Burgan and claimed "Burgan field is maturing fast."
Yep, there she goes! Cantarell slips under the waves.
Cantarell´s daily production in February was 1.567 million barrels, an 18 percent drop from 1.912 million barrels in February 2006 and a 1.5 percent slide from 1.591 million barrels in January, according to the Energy Secretariat´s web site.
That isn't far off their projected 14% decline per year... not a good thought either way though, is it?
"You can never solve a problem on the level on which it was created."
Albert Einstein
I ran -18% for 6 years. Came up with .476 million barrels in 2013. A drop of over 2/3.
Was this part of their OPEC cut or a genuine production drop due to lack of drilling initiative or terminal depletion curve?
There is no question that Cantarell is in terminal decline. It is freely admitted.
Mexico is not an OPEC member.