ABSTRACT: Oil and gas resource assessment of S.E. Asia and Australia

McCabe, Peter J.¹, Michele G. Bishop², Robert T. Ryder³, and Thomas S. Ahlbrandt⁴
(1) U.S. Geological Survey, Denver, CO 
(2) Contractor to the U.S. Geological Survey, Boulder, CO
(3) U.S. Geological Survey, Reston, VA
(4) U. S. Geological Survey, Denver, CO

The U.S. Geological Survey has recently conducted an assessment of oil and gas resources of the world and estimates of undiscovered resources were released in July 2000. The assessment entailed delineation of geologic provinces for the world and identification of the 76 provinces that contain 95% of the world's known petroleum resources. Several additional provinces were also assessed as possible future major petroleum provinces. An integrated study of source rocks, maturation and migration, reservoir rocks, seals and traps, allowed a detailed petroleum system analysis of each geologic province. This was used as a basis to predict undiscovered resources.

The current assessment suggests that there is considerably more undiscovered natural gas in the region than was estimated in the previous USGS world energy assessment, especially offshore northwest Australia. Turbidite complexes, incised valley-fills, deep-lacustrine clastics, nearshore marine sandstones, and reef-trend carbonates may be significant reservoirs in under-explored plays. Inversion structures and tilted fault-blocks associated with rifts have been successful targets for exploration over the last decade and such structures are thought to contain significant undiscovered hydrocarbon accumulations. Future additions to reserves will also result from field growth that may occur, for example, from better recovery techniques and better understanding of complex reservoirs such as highly compartmentalized shoreface-sandstones.

AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia