As Figure 3.3 shows, there have since the 1940s been a large number of estimates of ultimately recoverable oil. At that time the world was thought to have less than 100Gtoe (730 billion barrels). Estimates rose rapidly in the late 1940s and throughout the 1950s and 1960s, as the global oil industry not only expanded geographically, but also increased its intensity of development. Most notable, of course, in this latter respect was the Middle East which was exploited on a large scale for the first time during that period. By 1970 estimates of ultimate global reserves had settled down at around 300Gtoe (2,200 billion barrels) leading to a major fear of scarcity in the context of the widely held belief that this figure represented the ultimate truth on the future availability of oil (Warman, 1972); albeit a view of the limited prospects which was challenged by other observers (Odell, 1973; Styrikovich, 1977; Odell and Rosing, 1980). Since then, however, the hitherto rapid increase in the demand for oil from 1950 to 1973 (averaging 7.5% per annum) fell sharply, so significantly undermining the previously perceived need for large volumes of future supplies. Meanwhile, interest in the ultimate reserves of the Middle East evaporated with the nationalisation of the international oil companies in most of the countries in the region. Instead, a more intensive appraisal of the oil wealth elsewhere in the world became of greater interest in both the industrialised and the developing countries...