Deterministic vs Probabilistic well planning method

The ability to show the management that the calculated well costs are based on realistic drilling operations and prices for services, is important as this allows them to see that the risks have also been identified and quantified.

Clearer overview of well costs’ division gives a higher level of confidence for the drilling investment decision to be made by the management.

Probabilistic vs Deterministic Well Planning

There is some confusion as to what the difference is between probabilistic and deterministic well planning.

The normal deterministic well planning approach allows for only one course of well planning events. This approach makes it very hard to address all of the risk possibilities that may arise during a drilling operation.

Using probabilistic well planning based on a simple spreadsheet offers benefits of ranges for drilling time and cost, it is, however, difficult to enter information on the different paths that may present themselves during planning a drilling operation.

Using probabilistic drilling engineering software that is designed for drilling operations allows the well team to simulate and identify various operational paths and assignment of probability of their occurring.

By applying AGR’s iQx PLANS™ software, the drilling teams are able to achieve a comprehensive understanding of the time-cost risk spread in well projects. This can help provide detailed answers to the three basic questions in managing well investment decisions:

• What is the likelihood of overrunning the budget?
• What is the level of exposure associated with any overrun that may occur?
• Where do the individual risks lie that need to be mitigated against in order to avoid overrun?