An Integrated Approach to Evaluate the Further Development of the Changbei Unconventional Tight Gas Reservoirs

Shell and PetroChina have been successfully developing the Main Changbei P1S2 QA Reservoir using the advanced technology of openhole dual lateral horizontal wells since 2005. The scope of this project has been expanded to further develop the Changbei Main Reservoir and also to appraise and develop the Unconventional tight gas Reservoirs. The Unconventional tight gas Reservoirs have not been commercially developed to date and are geologically very different from the Main Reservoir. The team employed front end loading and decision based modelling to manage the complexities of essentially developing a green field within a brown field, and unconventional microDarcy reservoirs above and below a more conventional milliDarcy reservoir. The field was divided into type areas based on reservoir quality and development maturity. The Main Reservoir modelling approach is conventional but the Unconventional Reservoirs will require single-well multi-reservoir box models to facilitate probabilistic uncertainty work flows and type curve generation. Synergies between the Main and the Unconventional Reservoirs have also been considered.