West Siberian’s reserves increased by 48%

In 2007, West Siberian Resources Ltd successful exploration and development program added net proven and probable oil reserves of 64.8 million barrels. The net proven oil reserves increased by 48 per cent to 162.9 million barrels. Proven and probable (2P) reserves increased by 18 per cent to 361.0 million barrels. The increase in 2P reserves represents an internal reserve replacement ratio of 609 per cent. 3P reserves (proven, probable and possible) increased to 487.0 million barrels (443.9) million barrels.

West Siberian’s oil reserves have been revised following a recent independent reserve appraisal conducted byDeGolyer and MacNaughton, in accordance with reserve definitions consistent with those approved in March 1997 by Society of Petroleum Engineers (SPE). DeGolyer and MacNaughton is a leading international petroleum consulting firm with an extensive reserve estimation practice in Russia.

Since last years reserve report, proven and probable oil reserves of 64.8 million barrels were added through exploration and development drilling as well as reserve revisions. Including the possible category, total oil reserves increased by 12 per cent to 487.0 million barrels. The increase in 2P reserves of 64.8 million barrels indicates that 609 per cent of the total 2007 oil production of 10.6 million barrels was replaced.