Assessing Unconventional Resources Using an Integrated Petroleum Systems Approach

Petroleum system modeling has matured in the past few years and is now a valuable component in conventional exploration. It has become best practice to mitigate risks by using petroleum system modeling to predict the presence, types, and volumes of hydrocarbons in prospective areas or structures before drilling. An adaptation of this methodology has been successfully applied to unconventional resource plays. Petroleum system modeling may be applied to predict: the type and quantity of hydrocarbon remaining in the source rock, proportion of adsorbed gas, porosity, and geomechanical properties of potential unconventional reservoirs. A new methodology has been developed to integrate trap, reservoir, charge, seal, and other risk (sub-) elements to evaluate play risk. Chance-of-success (COS) maps are created by transforming the physical propertiy maps to maps with probability units. As data, interpretations and related COS maps are in the same software system, the evaluation can be kept alive and dynamic as new data interpretations become available. Within the same application, prospect COS can be evaluated using a consistent approach This paper illustrates this methodology using examples from shale plays in North America, data-rich plays from the North Slope of Alaska and data-poor plays that are more representative of many Asia-Pacific basins from the north-eastern and southern regions of the United States. The examples demonstrate the application of the methodology in both frontier and mature areas, either in quick data-room reviews or for delineating prospects.