Copyright 2004 G.R. Morton. This can be freely distributed so long as no changes are made and no charges are made.
There are four oil fields in the world which produce over one million
barrels per day. Ghawar, which produces 4.5 million barrels per day,
Cantarell in Mexico, which produces nearly 2 million barrels per day,
Burgan in Kuwait which produces 1 million barrels per day and Da Qing
in China which produces 1 million barrels per day. Ghawar is,
therefore, extremely important to the world's economy and well being.
Today the world produces 82.5 million barrels per day which means that
Ghawar produces 5.5 percent of the world's daily production. Should it
decline, there would be major problems. As Ghawar goes, so goes Saudi
Arabia.
The field was brought on line in 1951. By 1981 it was producing 5.7
million barrels per day. Its production was restricted during the 1980s
but by 1996 with the addition of two other areas in the southern area
of Ghawar brought on production, Hawiyah and Haradh, the production
went back up above 5 million per day. In 2001 it was producing around
4.5 million barrels per day. There have been 3400 wells drilled into
this reservoir
I have noted elsewhere that the data I am being told by engineers who
have actually worked on Ghawar, that this decade will see it's peak.
(Morton, 2004 PSCF in press). Others have noted how the percentage of
water brought up with the oil has been growing on Ghawar. There are
published reports that Ghawar has from 30-55% water cut. This means
that about half the fluids brought up the well are water. Today the
decline rate is 8%. Thousands of barrels per day of production must be
added each year.
"The big risk in Saudi Arabia is that Ghawar's rate of decline
increases to an alarming point," said Ali Morteza Samsam Bakhtiari, a
senior official with the National Iranian Oil Company. "That will set
bells ringing all over the oil world because Ghawar underpins Saudi
output and Saudi undergirds worldwide production." JEFF GERTH,
"Forecast of Rising Oil Demand Challenges Tired Saudi Fields," February
24, 2004 New York Times, Late Edition - Final , Section A , Page 1 ,
Column 3 www.peakoil.net/Newspapers/20040224NYTTiredSaudiFields.doc
Unfortunately for the world, few know the actual state of Ghawar.
Cumulative production from the field is 55 billion barrels. In 1975
Exxon, Mobil, Chevron and Texaco estimated that the ultimate recovery
from the field would be 60 billion barrels. Without a doubt, new
technologies have moved EURs from that which was possible in the mid
1970s. But the Saudis claim that the field can recover another 125
billion barrels.(this info come from www.simmonsco-intl.com/files/IEA-SOM.pdf
slide 25 accessed 7-5-04) For someone like me who has spent a lifetime
in the oil industry trebling the recovery factor is a fantasy we all
wish we could do. But no one has ever figured out how. Thus, I doubt
very much their claims, especially in light of the maps shown below.
But this is what is happening
"Saudi oilmen are usually a taciturn bunch, guarding their data like
state secrets. But this was post September 11 and Riyadh was wooing
western journalists and trying to restore the Saudis' image as
dependable, long-term suppliers of energy--not suicidal fanatics nor
terrorist financiers. And it was working.
"Then the illusion slipped. On a whim I asked my hosts about
another , older oilfield called Ghawar. It is the largest field ever
discovered, its deep sandstone reservoir at one time had held perhaps
one-seventh of the world's known oil reserves, and its well produced
roughly one of every 12 barrels of crude consumed on earth. In the
iconography of oi, Ghawar is the mythical giant that makes most other
fields look puny and mortal. . . .
"At Ghawar,' he said, 'they have to inject water into the field to
force the oil out,' by contrast, he continued, Shayba's oil contained
only trace amounts of water. At Ghawar, the engineer said, the 'water
cut' was 30%."
"The hairs on the back of my neck stood up. Ghawar's water
injections were hardly news, but a 30% water cut, if true, was
startling. Most new oilfields produce almost pure oil or oil mixed with
natural gas--with little water. Over time, however, as the oil is drawn
out, operators must replace it with water to keep te oil flowing
--until eventually what flows is almost pure water and the field is no
longer worth operating."
"Ghawar will not run dry overnight, but the beginning of the end
of its oil is in sight." Paul Roberts, "New Tyrants for Old as the Oil
Starts to Run Out, " Sunday Times (News Review), May 16, 2004, p. 8
But this year at the Offshore Technology Conference some were talking
about a 55% water cut for Ghawar. Part of this is because the Saudi's
inject large quantities of water into the reservoir and much of it
comes back to the producing wells immediately though the system
"Saudi Aramco is injecting a staggering 7 million barrels of sea water
per day back into Ghawar, the world's largest oilfield, in order to
prop up pressure. It accounts for 30% of Saudi oil reserves and up to
70% of daily output." "Doubts grow about Saudi As Global Swing
Producer," Aberdeen Press & Journal Energy, April 5, 2004, p. 15
But several people are becoming concerned about the ability of the
Saudi's to maintain production. Here is a tidbit from the Aberdeen
Scotland Newspaper of a few weeks ago.
"It seems a growing number of analysts are falling into line with the
Simmons & Company International view that Saudi Arabia may be
running out of steam and may not be able to perform the role of global
swing producer for many more years, despite being credited with oil
reserves in the order of 260 billion barrels. The Centre for Global
Energy Studies hinted at the beginning of the year that the kingdom
appeared to be heading for difficulties. Now one of its analysts has
said that having reserves does not equate to production capacity.
Citing the Haradh field, he said it required 500,000 barrels per day of
water injection to get out 300,000 bpd of oil. Moreover the problem is
even more serious in the Khurais field." "Doubts grow about Saudi As
Global Swing Producer," Aberdeen Press & Journal Energy, April 5,
2004, p. 15
Since I am more and more working in the area of reservoir management,
one of the things I have learned is that when you have to inject 500k
barrels of water to get 300k barrels of oil, you will cycle water
through that field like crazy. You won't up the pressure so you are
probably cycling at least 200,000 barrels per day of water through the
field.
For those who don't think there is a problem with the Saudi production,
here are a couple of pictures of Ghawar from a 1996 report which shows
the size of a 3d seismic section on the overall Ghawar field. The next
picture is from the 3D showing the injection wells and the line in 1996
where the water had encroachd.
See image: Uthmaniyah 3D seismic survey
The Uthmaniyah area is the oldest producing area on Ghawar. But the
next picture shows that to the right of the line the oil is gone and
all that is left is water The solid circles are or were oil producers.
the open circles with arrows through them are where the water is
injected to the reservoir to push the oil towards the producers (On the
picture below this is from the right to the left. You can see that in
this area, in 1996 the water had encroached halfway across Ghawar.The
water must have moved further to the west today, 8 years later.
See image: Ghawar Water Front
the various areas of Ghwar are outlined at a map found at web.inetba.com/gregcroftinc/images/Ghawar_map.gif
What is the future of Ghawar and Saudi production? It is not good.
"All production comes from 'very old fields', with no major exploration
success since the 1960s, and almost every field has high and rising
water cut.
"Saudi Aramco is injecting a staggering 7 million barrels of sea water
per day back into Ghawar, the world's largest oilfield, in order to
prop up pressure. It accounts for 30% of Saudi oil reserves and up to
70% of daily output." "Doubts grow about Saudi As Global Swing
Producer," Aberdeen Press & Journal Energy, April 5, 2004, p. 15
and
"The Wocap simulations for Saudi oil are presented in Fig. 5. They
clearly show a long plateau at 8-10 million b/d. Here the main question
is: How long can Saudi Arabia plateau at that level? Or in other words:
Will it age gracefully? Much will depend on Ghawar. “
“With 100 billion bbl of crude oil produced so far, Saudi Arabia
should not be far from the midway point of its proved reserves of 260
billion bbl—that means just 10 years at the going rate of roughly 3
billion bbl/year. Bearing in mind the "spurious revision" of 1990 that
boosted proved Saudi reserves to 257. billion bbl from 170 billion bbl,
the midway point could happen even sooner than that. “
“Furthermore, the 35 billion bbl produced during 1990-2002 has not
been accounted for, as Saudi "proved reserves" were still being
reported at 260 billion bbl by the close of 2001. “A. M. Samsam
Bakhtiari, “Middle East Oil Production to Peak within next decade.” Oil
and Gas Journal, July 7, 2003, p. 24
One of the interesting things about Ghawar is the nature of its
reservoir which provides an argument against an ideology I fight all
the time, Young-earth Creationism. Ghawar is largely made of dung,
which would be hard pressed to be concentrated during a global flood
and thus contradicts the young-earth creationist claims.
“Most massive and nonporous limestones contain textures made by
invertebrate animals that ingest sediment and turn out fecal pellets.
Usually, the pellets get squished into the mud. Rarely do the fecal
pellets themselves form a porous sedimentary rock. In the 1970s the
first native-born Saudi to earn a doctorate in petroleum geology
arrived for a year of work at Princeton. I used the occasion to twist
Aramco’s collective arm for samples from the supergiant Ghawar field.
As soon as the samples were ready, I made an appointment with our Saudi
visitor to examine the samples together using petrographic microscopes.
That morning, I was really excited. Examining the reservoir rock of the
world’s biggest oil field was for me a thrill bigger than climbing
Mount Everest. A small part of the reservoir was dolomite, but most of
it turned out to be a fecal-pellet limestone. I had to go home that
evening and explain to my family that the reservoir rock in the world’s
biggest oil field was made of shit.” Kenneth S. Deffeyes, “Hubbert’s
Peak” (Princeton: Princeton University Press, 2001), p. 57-58
Back to the serious issue of Ghawar, an almost poetic ode to the death of Ghawar can be found at www.newcolonist.com/ghawar.html. As Ghawar goes, so goes the world.
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Published on 29 Jul 2004 by DMD Publishing. Archived on 29 Jul 2004. Trouble in the World's Largest Oil Field-Ghawarby Glenn Morton FAIR USE NOTICE: |

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