Saudi Arabia controls nearly $16.9 trillion (Dh62trn) worth of oil reserves under its arid sands but the wealth could sharply rise with the advent of more advanced production technology, a key Saudi bank said yesterday.

The National Commercial Bank (NCB) said the kingdom's oil resources that can be recovered by present technology are estimated at around 260 billion barrels but they account for just a fraction of the real oil deposits.

In a short study sent to Emirates Business, NCB estimated Saudi Arabia's total crude resources in place at more than 742 billion barrels, including those which can not be reached by present production and drilling techniques.

"Only a fraction of this oil can be brought to the surface on limitations of petroleum extraction technologies and the typical structure of the reservoir… at the end of 2008, Saudi Aramco's oil and gas reserves were spread over 104 fields of which only 23 were in production," it said.

These fields have so far known 354 different reservoirs with a combined capacity of more than 742 billion barrels of discovered oil resources in place, including proven, probable and possible reserves.

"At the end of 2008, the remaining proven reserves composed roughly 260 billion barrels of the total oil in place," the study said.

"Assuming a crude oil production rate of 8.9 million barrels per day, these proven reserves could deplete in the next 80 years. At an average crude oil price of $65 a barrel, the market value of these reserves is estimated at about $16.9trn.

"Moreover, at the fixed level of 2009 budgetary outlays, this amount could last for the next 133 years."

Saudi Arabia is the world's oil powerhouse, controlling nearly a quarter of the global proven crude deposits and pumping 10 per cent of the world supply. Despite its massive proven oil wealth, the government-owned Saudi Aramco is pushing ahead with an ambitious programme to increase extractable crude resources along with other projects to expand output capacity.

The drive is within a massive development programme that involves investment of more than $100bn to boost output to 12.5 million bpd by the end of this year and 15 million bpd in the next five years. It also includes expansion of the country's refining and petrochemical production.

"As most of you know, Saudi Aramco manages the world's largest proven reserves of crude oil and its fourth largest concentration of natural gas reserves. Rather than rest on our laurels, however, we continue our efforts to discover and define additional quantities of both oil and gas, and to continue to bolster our reserves of these precious energy resources," Abdulaziz Al Khayyal, Saudi Aramco Senior Vice-President for Industrial Relations, said.

"Despite our tremendous reserve base, we are pressing ahead with an ambitious exploration programme, and are continuing to push the envelope when it comes to reservoir delineation and reservoir management activities, which help us to identify and produce additional hydrocarbon reserves within known fields."

Khayyal said the programme runs parallel to another major investment drive targeting the country's production and export terminal capacity with the aim of expanding Saudi Arabia's supply potential and meet future global demand.

Figures by the 10-nation Organisation of Arab Petroleum Exporting Countries showed Saudi Arabia has around 87 billion barrels of accessible but untapped oil resources, nearly 49 billion barrels of condensates and about18 trillion cubic metres of natural gas.

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