Upper Zakum offshore oil field is located approximately 84km off the coast of Abu Dhabi, UAE. With estimated proven crude oil reserves of 50 billion barrels, Upper Zakum is one of the world’s biggest oil fields.
The giant offshore oil field covers more than 1,150km² in water depths of 6m-13m in the Persian Gulf and extends up to 8,000ft below the sea bed.
Upper Zakum is also one of the world’s most innovative offshore oil field to have adopted artificial island-based development concept, and advanced reservoir simulation and extended-reach drilling technologies to steadily boost its production capacity.
The field’s production capacity increased from 500,000 barrels per day (bpd) in 2006 to 750,000bpd at the end of 2017. It is expected to further increase to one million bpd by 2024 and continue until at least 2050.
Upper Zakum oil field is owned by Zakum Development Company (ZADCO), a joint venture of Abu Dhabi National Oil Company (ADNOC, 60%), ExxonMobil (28%), and Japan Oil Development Company (Jodco, 12%), a wholly-owned subsidiary of INPEX.
ADNOC has been the operator of the offshore oilfield since it commenced production in 1982.
Upper Zakum offshore oil field discovery and development history
Following the discovery of Upper Zakum oil field in 1963, ZADCO was formed in November 1977 to develop the field, in which ADNOC held 88% interest and INPEX the remaining 12% stake.
The field was brought on stream in 1982 and has 450 wells tied-back to approximately 100 offshore platforms to attain the 500,000bpd production capacity as of 2006.
ExxonMobil joined the Upper Zakum offshore oil field development by acquiring 28% interest in ZADCO from ADNOC in 2006.
The partners in ZADCO started exploring artificial island-based development options in the same year, in order to increase the production to 750,000bpd with the use of extended-reach drilling technology to increase oil recovery, while minimising infrastructure needs.
Upper Zakum redevelopment details
The construction of artificial islands started soon after the completion of feasibility study in 2010.
The key contracts for the production and processing facilities of the $10bn redevelopment project called UZ750 Project at Upper Zakum were awarded in 2012 and 2013.
The construction of the island was completed in 2014 and production from one of the newly built islands commenced in the same year.
The production capacity reached 750,000bpd with the installation of all modules on the islands, in 2017.
Infrastructure facilities for Upper Zakum redevelopment
Upper Zakum oil field has been redeveloped with four oval-shaped artificial islands measuring 2,000ft to 2,600ft in diameter.
The central island measuring 1,200mx600m is the biggest island on the field and houses the processing facilities, while the north, west and south islands are used as satellite platforms.
The construction of the islands involved 23.5 million cubic meter of dredging, 14 million tonnes (Mt) of rock and 13.5 million cubic feet of concrete.
The island-based infrastructure allows for the use of higher-capacity land-based drilling rigs. It currently has 1,000 well slots located on four islands of the oil field with well lengths up to 35,000ft.
The artificial islands are installed with more than 100 different modules including up to 22 production modules comprising a wellhead control and oil processing unit as well as pipe racks, other process modules, buildings and substations.
The other facilities on the islands include riser platforms, flare towers and bridges, water injection and gas lift facilities, booster gas compression facilities, oil export pumps, and power generation and ancillary utilities including permanent accommodations for 2,500 people.
The redevelopment project also involved the installation of 32 new pipelines and 300 pipeline crossings.
The crude oil produced from the central island is pumped to the Zikru Island via a 55km-long pipeline for further processing.
Upper Zakum oilfield expansion details
In November 2017, the Upper Zakum development partners announced the plan to increase the oil field’s production to one million bpd by 2024.
The capacity expansion will be achieved by drilling additional wells using extended-reach drilling and maximum reservoir contact well technologies. Eight drilling rigs are currently operating from the four artificial islands of the oilfield.
The advanced technologies have been successfully used for the recently completed UZ750 project at Upper Zakum, delivering higher production rates from fewer wells while improving oil recovery and reducing capital expenditure.
Extended-reach drilling technique will enable the drilling of long-reach horizontal wells of more than 9.6km length from the artificial islands while minimising the environmental footprint.
Reservoir characterisation and simulation with the use of computational well modelling will provide maximum reservoir contact for efficient oil production.
Contractors involved with Upper Zakum oilfield development
Ramboll was contracted for the feasibility study of the artificial islands at Upper Zakum offshore oilfield in 2009. National Marine Dredging Company (NMDC) was awarded the construction contract for the islands in 2010.
AMEC was awarded a $75m project management consultancy (PMC) services contract for the offshore components of the Upper Zakum development project in September 2008, while COWI was awarded the PMC service contract for the construction of the artificial islands.
Amec Foster was awarded an extension contract for its project management services, in August 2015.
Technip was awarded the front-end engineering and design (FEED) contract for the processing units on the four artificial islands at Upper Zakum in March 2011.
Technip, in a consortium with National Petroleum Construction Company (NPCC), was awarded an $817m engineering, procurement, construction, installation (EPCI), commissioning and start-up contract for the UZ750 Project, in August 2012.
The contractual scope included 240km of subsea pipelines, 128km of subsea composite and fibre-optic cables, and offshore structures including jackets, riser platforms, flare towers and bridges.
Petrofac Emirates, along with Daewoo Shipbuilding & Marine Engineering (DSME), was awarded a $3.7bn engineering, procurement, construction (EPC), transportation and commissioning contract for island surface facilities including wellhead control, manifolds, crude oil process facilities, water injection and gas lift, oil export pumps, power generation and associated utilities on four artificial islands at Upper Zakum in April 2013.
ALE was subcontracted for the transport of different modules to the islands of the Upper Zakum oil field.
Habtoor Leighton Group (HLG) was awarded the construction contract for the accommodation and support facilities on the artificial islands in June 2012.