High petroleum prices have stimulated worldwide exploration. Better understanding of the basic principles of the origin and primary migration of hydrocarbons and of basin tectonic processes have aided in selecting areas that warrant intensive exploration. There is renewed interest in oil prospects of overthrust belts, and attention has been drawn to the high potential of buried Late Tertiary reefs in tropical regions. Advances in seismic data gathering and processing have greatly increased the usefulness of geophysical surveys, once essentially limited to the search for closed structures.

Since 1979, oil production has been found in previously unproductive basins, such as the Grand Banks of Newfoundland, and even in newly discovered basins, including southwestern Sudan and the Gulf of Beibu (Tonkin) off southern China. The most significant oil discovery in recent years is the Hibernia field off Newfoundland. Large gas fields have been found in the Norwegian sector of the North Sea, off Cameroun in West Africa, onshore and offshore in Spain, and in Sharjah on the Arabian Peninsula. Numerous other fields have been found throughout the world, but data are insufficient for estimating the size of many of these discoveries, even though some will certainly prove to be in the giant class. Data on the Soviet Union are insufficient for commenting on recent exploration results. >

Companies have been granted large new contract areas for petroleum exploration in many countries, some of them in basins already surveyed in reconnaissance, others untouched by modern geophysical methods. Availability of new land rights ensures that the present drive for new oil and gas resources will continue in future years, probably with a similar degree of success.