unproven reserves the estimated quantities at a specific date, which analysis of geologic and engineering data indicates might be economically recoverable from already discovered deposits, with a sufficient degree of probability to suggest their existence; because of uncertainties as to whether, and to what extent, such unproven reserves may be expected to be recoverable in the future, the estimates should be given as a range but may be given as a single intermediate figure in which all uncertainties have been incorporated GRM: pl.n. References: GENreserves SEEproven reserves SPEpossible reserves SPEprobable reserves