We report work carried out within the CODIO project on COllaborative Decision support for Integrated Operations. As one part of this project, we have designed a system to provide assistance in operational decisions based on real-time sensor readings in a typical scenario: while drilling close to the transition to a high-pressure formation, a gas influx is observed. The drilling team needs to decide whether to circulate, increase the mud weight, plug back, set a casing, etc.
After a brief description of the technology we used to model decision problems (Bayesian Networks, Influence Diagrams), we describe our case study and go on to apply the method of decision analysis to it. We discuss how the resulting influence diagram was tested using a simulation, and discuss challenges in applying the technology, as well as lessons learnt underway. We also give a list of desiderata to establish better decision making practices in the petroleum industry.