Abstract: Petroleum Development Oman Gas Exploration Unlocks Major New Reserves

Andrew Wood, Antonio Mozetic

Since 1985, Petroleum Development Oman (PDO) has been exploring for gas on behalf of the Government of Oman under a ten-year agreement signed in June 1984. The aim of the one-rig programme was to find additional non-associated gas reserves (3 TCF) to meet domestic energy requirements for a minimum of 40 years, for which the available reserves at that time (5.6 TCF) were insufficient.

Initial results of the campaign, which principally targeted the Permian Khuff Formation, were disappointing, analogues to the major accumulations of the Arabian Gulf failing to materialise. During the second half of the programme, therefore, the strategy was revised to address the prospectivity of higher risk/higher reward plays recognised at greater depths.

Well Saih Nihayda-24, drilled in 1989, found gas/condensate-bearing reservoirs in Cambro/Ordovician sandstones of the Andam Formation below 4000 metres. This discovery, in a seismically poorly defined anticline, sparked an intensive effort of 2D, and later 3D, long cable seismic acquisition. This led in 1991 to additional major gas/condensate finds in Saih Rawl and Barik, and a dedicated two-year two-rig appraisal campaign has since proven up sufficient reserves to support an LNG gas export scheme.

The ten-year programme has more than tripled Oman's non-associated gas expectation reserves to some 22 TCF, exceeding the target more than five-fold. Significant potential for further gas discoveries identified in both North and South Oman provides encouragement for continued successful gas exploration in the future.

AAPG Search and Discovery Article #90956©1995 AAPG International Convention and Exposition Meeting, Nice, France