This talk addresses the relatively new area of Resource Play evaluation. The question of “what is a Resource Play?” is extensively discussed including the four identifying characteristics (repeatable statistical distribution, behavior of offset well performance, a continuous hydrocarbon system, lack of hydrodynamic support) and the reservoirs which are most commonly Resource Plays (shale gas, coalbed methane, tight gas, basin centered gas systems, certain tight oil). Statistical analysis is introduced in a fashion that treats statistics as a practical tool, rather than a complex mathematical system, with actual oil field examples offered. We review common data distributions (normal and lognormal) using examples of actual oil field data. The probability graph is of particular importance as are the concept of aggregation of wells, and the SPE reserve definitions using probabilistic methods. We examine ways to use Monte Carlo modeling to estimate Proved, Probable, and Possible reserves. However an alternative method to estimate probabilistic reserves using deterministic data, when Monte Carlo techniques are unavailable, is explored.
The primary goal of this discussion is to help the evaluator understand the concept of probabilistic reserves and how Resource Plays are best evaluated using statistical methods.