Arab countries control nearly 43 trillion cubic metres (tcm) of additional gas deposits but they remained undiscovered or untapped, their oil group has said.

More than half of the undiscovered gas resources are based in Saudi Arabia and Iraq while other large quantities are concentrated in the UAE, Algeria, Qatar, Libya, Egypt and Kuwait.

Around 197 billion barrels of crude oil have also remained underground unexploited in the region, most of which are in Saudi Arabia, Iraq, the UAE, Algeria and Libya, the 10-nation Organisation of Arab Petroleum Exporting Countries (OAPEC) said in a study.

It put the total Arab extractable oil reserves at 672 billion barrels and gas at 54 tcm at the beginning of 2009 but said massive quantities are either undiscovered and untapped or inaccessible by present technology.

"Large quantities or crude oil, condensates and natural gas have remained undiscovered in the Arab region… they are estimated at around 43.4 tcm of gas, 197.5 billion barrels of crude and 68.2 billion barrels of condensates," it said.

A breakdown showed undiscovered gas and oil reserves are estimated at 18.1 tcm and 87.1 billion barrels respectively in Saudi Arabia, which already controls in excess of 25 per cent of the world's total recoverable crude deposits. The Kingdom, the world's largest oil exporter, is also believed to have some 48.9 billion barrels of undiscovered condensates.

Undiscovered hydrocarbon resources in Iraq were put at around nine tcm of gas, 45.1 billion of crude and 6.2 billion of condensates.

In the UAE, they stood at 1.26 tcm of gas, 7.7 billion barrels of oil and 2.4 billion barrels of condensates. They were estimated in Kuwait at 194 billion cubic metres of gas, 3.8 billion of crude and four billion of condensates.

Qatar, the world's third largest gas power, has 1.16 tcm of undiscovered gas deposits, 3.6 billion barrels of oil and 5.4 billion barrels of condensates.

Undiscovered deposits in non-Opec Oman are estimated at nearly 956 billion cubic metres of gas, 3.5 billion of oil and 1.8 billion of condensates. Outside the Gulf, Algeria has around 5.66 tcm of undiscovered gas resources, 7.7 billion of oil and 2.1 billion of condensates. Libya's undiscovered hydrocarbon wealth was estimated at 3.25 tcm of gas, 8.3 billion barrels of oil and 9.2 billion barrels of condensates. In Egypt, they were put at 1.84 tcm of gas and 3.1 billion barrels of condensates.

Although they have pumped in excess of 50 billion barrels of oil during 2003-08, Arab countries have managed to increase their proven crude reserves from 658 billion to 672 billion barrels, OAPEC said. The increase was a result of new discoveries in some member states, development of major fields and introduction of advanced technology.

Most of the increase was achieved in Sudan, where they jumped from less than one billion barrels to five billion barrels. The rest came from Saudi Arabia, Kuwait, and Libya, which boosted them by around two billion barrels each.

Gas reserves grew by around 1.7 tcm and the bulk of the increase was achieved in Kuwait, Saudi Arabia and Egypt, the report said.

Proven gas deposits of regional countries also grew to around 54.7 tcm at the start of 2009 from nearly 53 tcm at the end of 2003 despite their cumulative production of around two tcm during that period, the report showed.

It showed Arab states, mainly those in the Gulf, have pumped a staggering 302 billion barrels of oil since they started production more than 50 years ago.

"Assuming an extraction rate of 35 per cent, the Arab oil deposits in place could reach 2,738 billion barrels. This means the oil quantities that cannot be extracted by present technology are around 1,809 billion barrels, which are nearly 645 billion barrels above the world's proven oil resources… these quantities, if they can be extracted, will meet the world needs for 60 years," it said.

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