Depletion rate analysis of fields and regions: A methodological foundation

•Establishment of a theoretical foundation for depletion rate analysis.•Discussion on the connection to physical forces acting within the reservoir.•Empirical and statistical analysis of individual oilfields and regions.•The theory was found to be well supported by the data.•Discussions on the implications for peak oil.

This paper presents a comprehensive mathematical framework for depletion rate analysis and ties it to the physics of depletion. Theory was compared with empirical data from 1036 fields and a number of regions. Strong agreement between theory and practice was found, indicating that the framework is plausible. Both single fields and entire regions exhibit similar depletion rate patterns, showing the generality of the approach. The maximum depletion rates for fields were found to be well described by a Weibull distribution.Depletion rates were also found to strongly correlate with decline rates. In particular, the depletion rate at peak was shown to be useful for predicting the future decline rate. Studies of regions indicate that a depletion rate of remaining recoverable resources in the range of 2–3% is consistent with historical experience. This agrees well with earlier “peak oil” forecasts and indicates that they rest on a solid scientific ground.