Overview of Jansz-Io Field, Upstream Gorgon Project Start-up Results and Integrated Tabletop Planning Process

Affinito, Ralph (Chevron Australia Pty Ltd) | Boxall, John (Chevron Australia Pty Ltd) | Clough, Jonathan (Chevron Australia Pty Ltd) | Coletta, Angelina (Chevron Australia Pty Ltd) | Frontczak, John (Chevron Australia Pty Ltd) | Morrison, Alan (Chevron Australia Pty Ltd) | Pradhan, Vijay (Chevron Australia Pty Ltd) | Robinson, William (Chevron Australia Pty Ltd)



Integrated subsurface and facilities management, along with asset integrity and reliability, is a "must win" for flawless start-up and early operations. This consists of understanding and closing the value loop around the subsurface and facilities of an asset or connected set of assets. One of the tools Chevron Australia (Chevron) used to successfully start-up the Jansz field under the Gorgon project was an upstream integrated planning process.

An upstream integrated tabletop process evaluates and tests all plans and procedures that are in place for start-up and the early operating life of the asset, from the sand-face of the reservoir to the inlet facilities (for an upstream focus). This process aims to eliminate the gap between a flawless start-up, defined as reaching target performance as early and safely as possible, and what could be a troubled start-up. Start-up plans are presented based on the underpinning objectives, challenges and strategies from each of the key stakeholder groups. A suitably wide range of credible scenarios, targeting those with the greatest potential to cause significant upsets, are considered and tested to ensure that procedures and mitigation measures are both suitably understood by the relevant stakeholders and are in place. The process also helps define roles/responsibilities and build relationships between the subsurface, subsea, facilities and operation teams starting up the project.

The integrated tabletop process has a significant focus on reservoir management. Early production, staggered well start-ups and well planned production ramp-up activities can provide insight into completion efficiency, performance prediction, reservoir connectivity and reserves assessment. Operation’s objectives, especially for a liquefied natural gas (LNG) plant (successive start-ups, minimum intervention) are often at odds with reservoir management. The tabletop process enables alternatives to be evaluated striving for a balanced, value added start-up plan.

This paper goes through an overview of some of the key concepts required for a successful integrated tabletop process and results of the Jansz field and upstream system start-up. Integrated planning involving subsurface, subsea, flow assurance and facilities resulted in a flawless start-up of the field. Highlights of the results for each of these areas will help support future start-up efforts.