Ghawar Field

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Ghawar is an oil field in Saudi Arabia. It is located about 100 km WSW from the city of Dhahran in the Eastern Province. Measuring 280 km by 30 km, this is by far the largest conventional oil field in the world. The field is entirely owned and operated by Saudi Aramco, the nationalised Saudi oil company. Relatively little is known about Ghawar because the company and Saudi government closely guard field performance information and per-field production details. Available information is predominantly historical (pre-nationalization), from incidental technical publications, or anecdotal.

1 Geology
2 History
3 Production
- 3.1 Field Reserves
4 See also
5 References
6 External links

[edit] 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), sourced from the Jurassic Hanifa formation, a marine shelf deposit of mud and lime with as much as 5% organic material (1% to 2% is considered good oil source rock). The seal is an evaporitic package of rocks including impermeable anhydrite.

[edit] History

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.

[edit] Production

Approximately 60-65% of all Saudi oil produced between 1948 and 2000 came from Ghawar. Cumulative production to the end of 2005 was about 60 billion barrels (based on Croft). Currently, Ghawar is estimated to produce over 5 million barrels (800,000 m³) of oil a day (6.25% of global production).

Ghawar also produces approximately 2 billion cubic feet (56 633 693 m³) of natural gas per day.

[edit] Field Reserves

Saudi Aramco has stated that it has more than 71 billion barrels of proven reserves remaining. Some people, such as Matthew Simmons in his book Twilight in the Desert, suggest that production from the Ghawar field and Saudi Arabia, may soon peak. However, Simmons' work has been strongly criticised by Saudi Aramco officials such as Nansen Saleri.