Proven oil reserves in Saudi Arabia are the second largest claimed in the world, estimated to be 267 billion barrels including 2.5 billion barrels in the Saudi-Kuwaiti neutral zone. These reserves were the largest in the world until Venezuela announced they had increased their proven reserves to 297 billion barrels in January 2011. The Saudi reserves are about one-fifth of the world’s total conventional oil reserves.
Although Saudi Arabia has around 100 major oil and gas fields, over half of its oil reserves are contained in only eight giant oil fields, including the Ghawar Field, the biggest oil field in the world with an estimated 70 billion barrels of remaining reserves. Saudi Arabia maintains the world’s largest crude oil production capacity, estimated to be approx. 11 million barrels per day at mid-year 2008 and announced plans to increase this capacity to 12.5 million barrels per day by 2009.
Saudi Arabia produced 10.3 million barrels per day in 1980, and 10.6 million in 2006. At the beginning of 2008, the kingdom was producing in the region of 9.2 million barrels per day of oil. After US President Bush asked the Saudis to raise production on a visit to Saudi Arabia in January 2008, and they declined, Bush questioned whether they had the ability to raise production any more. In the summer of 2008, Saudi Arabia announced an increase in planned production of 500,000 barrels per day. However, there are experts who believe Saudi oil production has already peaked or will do so in the near future.
Despite its large number of oil fields, 90 percent of Saudi Arabia’s oil production comes from only five fields and up to 60 percent of its production comes from the Ghawar field.
Since 1982, the Saudis have withheld their well data and any detailed data on their reserves, giving outside experts no way to verify Saudi claims regarding the overall size of their reserves and output. This has causes some to question the current state of their oil fields. In a study discussed in Matthew Simmons’s book Twilight in the Desert, 200 technical papers on Saudi reserves by the Society of Petroleum Engineers were analyzed to reach the conclusion that Saudi Arabia’s oil production faces near term decline, and that it will not be able to consistently produce more than 2004 levels. Simmons also argues that the Saudis may have irretrievably damaged their large oil fields by over-pumping salt water into the fields in an effort to maintain the fields’ pressure and boost short term oil extraction amounts.
Diplomatic cables leaked during the United States diplomatic cables leak in 2011 revealed that Sadad al Husseini, the ex-head of Saudi Arabia’s oil monopoly Aramco, warned the US that the oil reserves in Saudi Arabia might in fact be 40% lower than claimed (300bn barrels).