AUSTRALIA'S PETROLEUM PROSPECTS: CHANGING PERCEPTIONS SINCE THE BEGINNING OF THE CENTURY

Abstract

Perceptions of Australia's petroleum prospectivity, both by the general public and by professional explorationists, have changed considerably over the years. By the 1920s there had already been a considerable change from the optimism of the early part of the century, engendered largely by gas and condensate indications in water bores drilled in the Roma area, to a comparatively pessimistic view due to the failure of numerous small drilling ventures, and to the published opinions of some overseas experts.

The public then remained generally apathetic or pessimistic about Australia's petroleum future until the Rough Range discovery in 1953 finally dispelled the myth that Australia was barren of producible oil. Rough Range proved to be the first of a series of discoveries which significantly upgraded industry and public perceptions of Australia's petroleum potential.

Other particularly significant discoveries were the Moonie oilfield in 1961, the Gidgealpa and Barracouta gas fields in 1963 and 1964, the giant King-fish and Halibut oilfields in 1967, gas/condensate and oilfields on the North West Shelf in 1971, the Strzelecki and Fortescue oilfields in 1978, and the Jabiru oilfield in 1983. Exploration of the Exmouth Plateau from the early 1970s onwards initially caused a significant increase in estimates of Australia's petroleum potential, followed by downward revisions in the early 1980s because of the failure of the Plateau to live up to expectations.

Perceptions of the prospects of some individual basins have also changed dramatically with time. Notable examples are the onshore Carnarvon Basin, the Georgina Basin and the Eromanga Basin.

The most significant change in methods of assessing Australia's prospectivity was the introduction of quantitative, probabilistic methods in the 1970s. BMR's current assessment is that we can expect to find an additional 2 400 million barrels of oil, 23 trillion cubic feet of gas, and 550 million barrels of condensate on the Australian continental plate (average estimates).