Breaking Barriers: Unlocking the Potential of the Offshore Victoria HPHT Tight Gas Discovery

Abstract Hydraulic fracturing campaigns on the Norwegian Continental Shelf (NCS) are most commonly executed in chalk formations, while numerous tight sandstone gas opportunities remain unexploited. Historically, technical and operational challenges have included achieving an environmentally compliant fluid for HPHT conditions, the relatively low efficiency of offshore hydraulic fracturing operations, and reluctance to rig up complex coiled tubing spreads on expensive semi-submersible rigs. Victoria is one of these discoveries, with pore pressures exceeding 800 bar and temperatures reaching 200°C, containing an estimated gas initially in place (GIIP) of 140 BCM. Discovered in 2000, but difficulty in identifying a commercially viable development solution resulted in the discovery being relinquished in 2018. However, advancements in oilfield technology and completion techniques now offer solutions to the challenges previously faced. Detailed geomechanics analyses of offset wells and fine-grid 3D fracture simulations were conducted to assess hydraulic fracture feasibility and potential fracture propagation in tight gas units. Results suggest that fractures could be successfully placed, covering up to 70% of the main target unit. Modern multi-stage completion technologies were modelled to confirm that hydraulic fracturing operations could be executed within typical maximum working pressures of fracturing and completion equipment. Efficiency improvements for a multi-stage campaign were considered, particularly the use of drill pipe manipulated sleeves for rapid screen-out recovery, eliminating the need for complex coiled tubing rig-ups. A qualitative assessment of fracturing fluid options was performed. Finally, reservoir simulation incorporating the resulting fractures was carried out to evaluate production potential for multi-well field development. This paper details the integration of the latest stimulation technologies, transforming these tight gas discoveries from complex and uneconomic to commercially viable and highly workable opportunities. In Victoria, reservoir simulation results predicted a recovery factor of 29%, or about 40 BCM, based on a six-well development scenario. The feasibility of multi-stage stimulation using drill pipe manipulated sleeves removes the necessity for complex coiled tubing rig-ups, significantly reducing campaign costs and operational complexity. These findings demonstrate that an economic tight gas development of the Victoria discovery is now viable with modern stimulation and completion technologies. On the NCS there are a further 7 major unlicensed tight gas discoveries. The methodologies and technological applications presented here provide a blueprint for unlocking these and other tight gas opportunities on the NCS.