Ghawar Field
Location of Ghawar Field
Country	Saudi Arabia
Region	Eastern Province
Location	Al-Ahsa
Offshore/onshore	Onshore
Coordinates	25°26′N 49°37′E / 25.43°N 49.62°E / 25.43; 49.62 (Centre approximation: 25°12′N 49°19′E / 25.20°N 49.31°E / 25.20; 49.31)
Operator	Saudi Aramco
Field history
Discovery	1948
Start of production	1951
Peak year	2005 (Contested)
Production
Current production of oil	3,800,000 barrels per day (~1.9×10^8 t/a)
Year of current production of oil	2019
Current production of gas	2,000×10^6 cu ft/d (57×10^6 m3/d)
Estimated oil in place	48,250 million barrels (~6.583×10^9 t)
Estimated gas in place	110,000×10^9 cu ft (3,100×10^9 m3)
Producing formations	Upper/Middle Jurassic, Upper/Lower Permian, Lower Devonian

External images
Ghawar Field map and regional setting
Regional cross section through Ghawar
Total Wells at Ghawar. Blue wells are waterflood injectors, red are production wells.

Ghawar (Arabic: الغوار) is an oil field located in Al-Ahsa Governorate, Eastern Province, Saudi Arabia. Measuring 280 by 30 km (170 by 19 mi) (some 8,400 square kilometres (3,200 sq mi)), it is by far the largest conventional oil field in the world,^[1] and accounts for roughly a third of the cumulative oil production of Saudi Arabia as of 2018.^[2][3]

Ghawar is entirely owned and operated by Saudi Aramco, the state-run Saudi oil company. In April 2019, the company first published its profit figures since its nationalization nearly 40 years ago in the context of issuing a bond to international markets. The bond prospectus revealed that Ghawar is able to pump a maximum of 3.8 million barrels (600,000 m³) per day—well below the more than 5 million barrels (790,000 m³) per day that had become conventional wisdom in the market.^[4][3]

Geology

Ghawar occupies an anticline above a basement fault block dating to Carboniferous time, about 320 million years ago; Cretaceous tectonic activity, as the northeast margin of Africa began to impinge on southwest Asia, enhanced the structure. Reservoir rocks are Jurassic Arab-D limestones with exceptional porosity (as much as 35% of the rock in places), which is about 280 feet (85 m) thick and occurs 6,000 to 7,000 feet (1,800 to 2,100 m) beneath the surface. Source rock is the Jurassic Hanifa formation, a marine shelf deposit of mud and lime with as much as 5% organic material, it is estimated that 1% to 7% is considered good oil source rock. The seal is an evaporitic package of rocks including impermeable anhydrite.^[5]

History

In the early 1940s, Max Steineke, Thomas Barger and Ernie Berg noted a bend in the Wadi Al-Sahbah dry riverbed. Measurements confirmed that the area had undergone geologic uplift, an indication that an oil reservoir may be trapped underneath. Oil was indeed found, in what turned out to be the southern reaches of Ghawar.^[6]

Historically, Ghawar has been subdivided into five production areas, from north to south: 'Ain Dar and Shedgum, 'Uthmaniyah, Hawiyah and Haradh. The major oasis of Al-Ahsa and the city of Al-Hofuf are located on Ghawar's east flank, corresponding to the 'Uthmaniyah production area. Ghawar was discovered in 1948 and put on stream in 1951.^[1][7] Some sources claim that Ghawar peaked in 2005, though this is denied by the field operators.^[8][9]

Saudi Aramco reported in mid-2008 that Ghawar had produced 48% of its proven reserves.^[10]

Extraction of crude oil

Approximately 60–65% of all Saudi oil produced between 1948 and 2000, came from Ghawar. Cumulative extraction of petroleum through early 2010, has exceeded 65 billion barrels (1.03×10¹⁰ m³).^[2] In 2009, it was estimated that Ghawar produced about 5 million barrels (790,000 m³) of oil a day (6.25% of global production),^[11] a figure which was later shown to be substantially overestimated.^[4]

As of 31 December 2018, total reserves of 58.32 billion barrels (9.272×10⁹ m³) of oil equivalent including 48.25 billion barrels (7.671×10⁹ m³) barrels of liquid reserves have been confirmed by Saudi Aramco. Average daily extraction was 3.8 million barrels (600,000 m³) per day.^[3]

Ghawar also produces approximately 2 billion cubic feet (57,000,000 m³) of natural gas per day.^[12]

The operators stimulate production by waterflooding, using seawater at a rate said to be around 7 million barrels (1,100,000 m³) per day .^[13][14] Water flooding is said to have begun in 1965.^[15] The water cut was about 32% in 2003, and ranged from about 27% to 38% from 1993 to 2003.^[16] By 2006, North Uthmaniyah's water cut was about 46%.^[17][18]

Energy content

Taking the 1.9×10⁸ tonnes (1.9×10⁸ long tons; 2.1×10⁸ short tons) production figure per year and the conventional energy density of crude oil (per the definition of the ton of oil equivalent) of 41.868 megajoules per kilogram (5.2753 kWh/lb)) the total thermal energy equivalent produced yearly by the oil field is roughly 7.955 exajoules (2.210×10¹² kWh), or 2,210,000 gigawatt-hours of thermal energy equivalent.

For comparison,

• North Antelope Rochelle Mine, the largest coal mine in the world, produced 85.3 megatonnes (84,000,000 long tons; 94,000,000 short tons) of coal (down from over 100 megatonnes (98,000,000 long tons; 110,000,000 short tons) in 2015) at 8,800 British thermal units per pound (20,000 kJ/kg) or 1.746 exajoules (4.85×10¹¹ kWh) of thermal energy equivalent.

• McArthur River uranium mine, the largest uranium mine in the world, produced 16.1×10⁶ pounds (7.3×10⁶ kg) of yellowcake in fiscal 2017, equivalent to roughly 6.2 kilotonnes (6,100 long tons; 6,800 short tons) of uranium metal or 4.46 exajoules (1.24×10¹² kWh) of thermal energy at a burnup of 200MWh/kg achievable in CANDU-type reactors, but much less in more widespread reactor designs.

• The largest solar farm in the world, Bhadla solar park in India, covering 57 square kilometres (22 sq mi) and boasting a nameplate capacity of 2255 MW would produce 71.11 petajoules (1.975×10¹⁰ kWh) of electricity at a capacity factor of 100% (i.e. if the sun were shining at peak intensity at all times), but given a more realistic capacity factor of 25%, it would produce 17.778 petajoules (4.938×10⁹ kWh) of electricity per year.

• The largest wind farm as of 2021, Gansu Wind Farm in China has a nameplate capacity approaching 8 GW with plans to ramp up to 20 GW.^[19] A 20 gigawatt power plant at 100% capacity factor could deliver 630.7 petajoules (1.752×10¹¹ kWh) of electric output per year. However, once again due to the weather-dependency and intermittency of wind power, capacity factors for onshore wind installations like Gansu are typically much lower, ranging at 15-35% depending on local factors. Per^[20] 250000 standard tons of coal will be replaced per year at full deployment, which is equivalent to 7.327 petajoules (2.035×10⁹ kWh).

The Ghawar oil field is thus the largest single supplier of primary energy on Earth.

Reserves

In April 2010, Saad al-Tureiki, Vice-President for Operations at Aramco, stated, in a news conference reported in Saudi media, that over 65 billion barrels (10.3 km³) have been produced from the field since 1951. Tureiki further stated that the total reserves of the field had originally exceeded 100 billion barrels (16 km³).^[21]

The International Energy Agency in its 2008 World Energy Outlook stated that the oil production from Ghawar reached 66 Bbo in 2007, and that the remaining reserves are 74 Bbo.^[11]

Matthew Simmons, in his 2005 book Twilight in the Desert, suggested that production from the Ghawar field and Saudi Arabia may soon peak.^[22]

When appraised in the 1970s, the field was assessed to have 170 billion barrels (27 km³) of original oil in place (OOIP), with about 60 billion barrels (9.5 km³) recoverable (1975 Aramco estimate quoted by Matt Simmons). The second figure, at least, was understated since that production figure has already been exceeded.^[22]