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Weekly UpdatesBerri, found in 1964 by Mobil, is an onshore and offshore giant. It has over 10 bn barrels of 32-34-39[degrees] API oils recoverable at relatively low cost. The field produces from several Fms of Upper and Mid-Jurassic, lying mostly at 8,300 ft. Its capacity has been raised from less than 700,000 b/d in 1990 to 1.15m b/d. Berri crudes are blended with lighter grades mostly produced from Abqaiq and the field's system can take crudes from Qatif. The export blend is AEL.
Berri's associated gas is being developed under a project, which includes expansion of its gas processing plant. This is MGS' third gas processing plant, the first two being at Shedgum and Uthmaniyah, and its capacity has been raised to 1,400 MCF/d. It has a unit to recover 280 MCF/d of ethane and 70,000 b/d of propane-plus, quantities of heavier NGLs and 3,300 t/d of sulphur. The project was completed in late 2005.
Saudi Aramco in mid-2007 gave a $200m contract for the Berri water injection and Qatif crude oil pipeline projects to Global al-Rushaid, a unit of Global Industries of the US. The project covers installation of water pipelines, two shore approaches and lateral pipelines and pre-commissioning work. Offshore installation was scheduled to start in September, with the project expected to last at least 12 months.
Abqaiq, a super-giant found in 1940, is said to have 17 bn barrels of oils recoverable at relatively low cost. They are reservoired in Upper and Mid-Jurassic Fms at 6,690 ft in most cases. The field was expanded in 1994 to produce 850,000 b/d of 35-37[degrees] API oils with 1.32-2.28% sulphur. This has added 165,000 b/d to the stream producing AEL. Work on Abqaiq has included horizontal drilling. Abqaiq's crudes and those of Berri and Shaybah are mixed at blending facilities built at Abqaiq to produce the AEL. These facilities are linked by pipeline to Shaybah field in the deep south-east.
Harmaliya, found in the 1950s, is producing 175,000 b/d.
The Main Fields Producing Heavier Oils: Saudi Aramco's mothballed capacity for AM and AH crudes is limited to 1.8m b/d, down from to 3.2m b/d in 2001 and 4.87m b/d in late 1993. They include small offshore fields shut in and many wells closed in the larger fields. There will be a further mothballing of field capacities producing heavy crudes as additional fields, including those in the Najd area south of Riyadh, come on stream in the next few years.
Safaniyah, by far the largest offshore oilfield in the world, was found in 1951 by Texaco (which in 1937 was the first to join SoCal - now Chevron - in Saudi Arabia as a 50% partner in Aramco. But now Taxaco is part of Chevron). Texaco discovered and developed other offshore fields containing heavy oil.
Safaniyah has over 15 bn barrels of proven oil reserves recoverable at relatively low cost. The oil is heavy, 27[degrees] API with 2.93-2.96% sulphur, and much of Safaniyah's 1.5m b/d capacity has been mothballed. Like most other offshore fields in the north-east, the oil is reservoired in Cretaceous sandstones and carbonates mainly at a depth of 5,100 ft.
(Texaco sold 50% of its US East Coast system to Saudi Aramco in 1988. The resultant JV Star Enterprise gave Texaco permanent access to 630,000 b/d of Saudi crude oil. In 1997 Shell, Saudi Aramco and Texaco combined their assets into a new JV called Motiva Enterprise. On Oct. 9, 2001, as Chevron's takeover of Texaco was finalised, Saudi Aramco bought half of Texaco's stake in Motiva, with Shell buying the other half. Thus Motiva now is owned 50-50 by Saudi Aramco and Shell - see OMT 16).
In 1996, Saudi Aramco brought some of the mothballed desalting units and other facilities at Safaniyah back into operation. They enabled the company to handle more AM from the Zuluf field. Reservoir pressure at Safaniyah, however, has begun to decline.
Zuluf, another offshore giant found by Texaco in 1968, has about 6.5 bn barrels of proven oil reserves in a Lower Cretaceous Fm at 5,800 ft. Its capacity is over 500,000 b/d, with another 200,000 b/d and two GOSPs mothballed. Saudi Aramco has planned to raise the field's capacity to 1.2m b/d. Of this a further 500,000-700,000 b/d has been earmarked for closure. Related facilities to upgrade the field's AH to AM have been built.
Manifa, an offshore giant south-east of Safaniya found in 1957, has 10 bn barrels of proven reserves. It produces 200,000 b/d of 28[degrees] API oil with 2.97-3.66% sulphur. Manifa oils come mainly from two reservoirs, a Lower Cretaceous containing a very sour 26[degrees] grade, and an Upper Jurassic having a 29[degrees] API oil with 2.97% sulphur. Manifa was first brought into production in 1964 by drilling eight wells (see omt14SaudiFieldsOct3-05) Plans to expand the field's capacity by 2011 to 900,000 b/d of heavy oil, 120 MCF/d of sour gas, 50,000 b/d of condensate and 950,000 b/d of water have been delayed by two factors: a rapid rise in project costs and uncertainty about two 400,000 b/d refineries proposed to be built at Yanbu' and Jubail to convert its crude into light fuels (see down14SaudiRefOct1-07).
Saudi Aramco has recently put back to the second quarter of 2008 the tender for the programme's gas plant package. It has opted to reissue the qualification notice for the fourth package, with contractors told it may push the overall bids back until April 2008. The company is to combine the package with facilities to be built as part of the $10 bn Karan gas field development. Saudi Aramco briefed contractors on the first three packages during a recent meeting in London and is expected to complete these tenders before embarking on the fourth package.
Dubai-based J. Ray McDermott in May 2007 got a four-year contract to engineer, procure, construct, install, hook-up and commission the new Manifa facilities. The US company then said fabrication of platforms, with a combined weight of over 16,700 tons, was to begin at Jebel Ali in September 2007. The project includes modification work which entails design, procurement, installation, hook-up and commissioning of communication packages on 26 existing platforms. Its job has to be completed by 2011.
Marjan, an offshore giant found in 1967 by Chevron, extends well into Iranian waters, where the field is known as Forouzan. Marjan forms an axis of fields off the Saudi coast, all in Cretaceous-to-Upper Jurassic Fms, which include Hamur, Maharah, Lawhah, and Hasbah. Marjan, producer of AM, has a working capacity of 270,000 b/d - with 300,000 b/d of its 570,000 b/d capacity mothballed.
Khursaniya, an onshore field found in 1956, has almost 3 bn barrels of proven oil reserves in an Upper Jurassic Fm at 6,560 ft. Khursaniyah is being developed as part of a mega-project including Abu Hadriyash and Fadhili fields. The three-field system is to be on stream by end-2007 to produce 500,000 b/d of AL and AEL.
In late July 2007, Saudi Aramco and the main contractors, Bechtel and Technip, signed a new agreement converting the three-field development's deal to lump-sum turn-key (LSTK) status. This was previously on a cost-reimbursable basis. Saudi Aramco then said the mega-project will still be completed on schedule by end-2007. The main part of the project is expected to hit that deadline but it is understood the gas component may not come on stream until early 2008. The complex will process up to 1,000 MCF/d of gas and the facilities will produce 550 MCF/d of sales gas and 195,000 b/d of ethane and NGLs. Saudi Aramco is said to have agreed a final price of $3.6 bn with Bechtel and Technip. About 70% of the project was complete by late July.
Khursaniya's first-phase capacity by 1994 had reached 150,000 b/d of AM, compared with 75,000 b/d in 1991 and 50,000 b/d in the late 1980s. But about 50,000 b/d of its existing capacity has been mothballed.
Abu Sa'fa, found in 1963, straddles Saudi and Bahraini waters. It has more than 5 bn barrels of proven oil reserves. The field, shared with Bahrain, was shut down by Saudi Aramco in April 1987. It was re-opened in recent years. Bahrain receives 150,000 b/d from Saudi Arabia as its share in production from the Abu Sa'fa.
Universal modular platforms were installed by end-August 2001 at Safaniyah, Zuluf, Marjan and Abu Sa'fa by J. Ray McDermott under a contract signed in May 1999. A 300,000 b/d GOSP was being installed by Snamprogetti whose work was completed in late 2004, as part of projects for the onshore Qatif oilfield (see above). Abu Sa'fa has 18 new platforms. Together with Qatif, the two fields now are producing 800,000 b/d of AL.
Saudi Aramco is focusing much of its Khuff gas development on the 9 TCF Karan field, 100 km north of Ghawar, where it is to produce 1,000 MCF/d in 2011. Foster Wheeler in mid-2007 won the joint FEED/PMC contract on the onshore portion of the field. The project is estimated to cost about $10 bn.
The Najd Fields: The Najd reservoirs have lower pressure than first thought. Since 1994, production has been affected by the encroachment of sand into the wells. Underground pumps installed at the fields have clogged up with sand, with the blockage occurring roughly every three months. To prevent production from falling below 200,000 b/d, Saudi Aramco has been hooking up new fields found in that area since 1994. The fields need gas reinjection to maintain reservoir pressure.
Most of the gas is produced from the Nu'ayyim field, where the crude has the highest gas-to-oil ratio among the Najd structures. A 75,000 b/d GOSP at the field has been built, together with underground pumps, to raise gas supplies for a modified EOR system at the Hawtah centre. Nu'ayyim is being developed to produce 175,000 b/d by 2009.
Recoverable reserves of oil and condensates in the Najd area have been estimated at 10 bn barrels. Saudi Aramco experts still point to an earlier estimate that the Najd fields could have up to 30 bn barrels of liquids and major reserves of natural gas. The liquids and gas are reservoired in Paleozoic Fms older than the Khuff, at depths ranging from 7,900 to more than 9,000 ft. Some reservoirs are more than 150 ft thick. About 85-90% of the liquids and gas tested had no traces of hydrogen sulphide. Some crudes are free of sulphur and have been tested as a motor fuel.
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