Decision Model And Risk Analysis For Multilateral Completion Design In A Challenging Deepwater Well In Italy Available to Purchase

The evaluation of drilling and completion projects in deepwater environment has become extremely critical over the last months. A new approach, taking into account both risks and opportunities is necessary in order to be able to select the most appropriate solution to maximize safe productivity and the economic value of the project. A challenging subsea well is planned to be drilled and completed in a deep offshore field in the Adriatic Sea (Italy). The application is extremely demanding being a deepwater multilateral intelligent well, with gas lift in sour environment. Different scenarios have been compared with regards to the available technologies for multilateral and intelligent completions. A probabilistic approach, taking into account technical, organizational and environmental issues has been adopted to assess all the uncertainties related to reservoir characteristics, well design and productivity in terms of duration and cost. A dedicated fault tree approach was deemed useful to focus on the combination of events leading to a potential branch loss and to calculate the associated probability. All uncertainties were then combined with production profiles into a technical unit cost ($/bbl). The workflow and the results are fully documented in this paper. Despite the complexity of the project under evaluation, this analysis has shown to be very effective in providing the management with a comprehensive picture to make the right investment decision at a given confidence level