Estimated additional amount in place is the indicated and inferred tonnage additional to the proved amount in place. The estimates are based on the results of geological and exploratory information about an area or on evidence of duplication or parallelism of geological conditions that occur in known deposits. Deposits, the existence of which is merely speculative, are not included. Estimated additional reserves recoverable is the quantity of the estimated additional amount in place which might become recoverable within foreseeable economic and technological limits. To compile this indicator data are needed on a country basis.
Available sources are national statistical offices and publications.
The lead agency is the United Nations Department of Economics and Social Information and Policy Analysis. Further Information World Energy Council. Survey of Energy Resources.