Abstract Natural gas occurs over a broad range of sedimentary basins, but major new discoveries will be concentrated in the Middle East and the USSR.
Current world proven recoverable reserves are estimated as 2300 tcf, and total ultimate recoverable reserves are thought unlikely to exceed 6000 tcf. Just over 10 % of this ultimate volume has been consumed.
Résumé Les gisements de gaz naturel se manifestent dans une grande variété de bassins sédimentaires, mais les plus importantes découvertes se concentreront dans le Moyen Orient et en URSS.
Les réserves mondiales récupérables actuellement identifiées sont estimées à 65000 milliards de m3. On estime que le total maximum des réserves récupérables a peu de chances de dépasser 170000 milliards de m3.
Jusqu'à présent, un peu plus de 10% de ce volume total a été consommé.
1. INTRODUCTION Despite the virtues of gas as a high-energy clean fuel, problems of distribution have-and will probably continue-to limit the main market to areas of high population and industrial concentration. The development of LNG technology has now rendered accessible to the international market various supplies previously too remote for exploitation.' We have attempted to compile a realistic set of worldwide gas reserves. The accuracy of such numbers is clearly very variable, in part due to the inaccessibility to us of the basic data and in part to the intrinsic difficulty of estimation given the complexities of nature and the lack of adequate wells to define many large fields. Also, it has to be said that much confusion has been caused by misuse of the term "reserves", which appears to mean many things to many people.
We have confined ourselves to economically recoverable reserves of marketable gas remaining in the ground in known fields. We have felt it desirable to use a somewhat broader definition of proven reserves than that used by the API and AGA, which by T. D. ADAMS, Regional Geologist, British Petroleum Company Ltd., London, England, and M. A. KIRKBY, General Manager, BP Petroleum Development Ltd., Aberdeen, Scotland presumably implies some reduction in confidence in the numbers. This course was necessary since many large fields in various areas are inadequately defined; nevertheless sufficient information may be available to permit a reasonably accurate estimate of reserves which will be more helpful than the much smaller volume which can be considered as fully proven.
Throughout this paper the abbreviation tcf is used to represent scf.
For a variety of reasons, it has not been possible for us to produce an independent estimate of the volume of condensate reserves. Major problems are lack of data, variability of recovery factor, and the options open to producers to vary the split of volatile components between the gas and liquid phases.
There is much interest in the volumes of "Ultimate", "Potential" or "Speculative" reserves, both