Publications

The giant Tunu gas field was initially developed using standard completion wells, where most reservoirs are perforated simultaneously and produced behind sleeves. Despite field complexity and numerous subsurface challenges, this strategy allowed ramping-up of field production to a high level using only a limited number of wells. Continued depletion of the field has led to new challenges (differential depletion, hydrocarbon identification, water production) and led to the need for well spacing reduction. Monobore and tubing-less well architectures were progressively introduced in order to reduce drilling costs while allowing the implementation of a new bottom-up perforation strategy. These completion types and the perforation strategy have numerous advantages compared to standard completions, in particular with respect to water management. Although the current progressive bottom-up perforation strategy of the Tunu wells implies a very important activity level, it is today considered as the optimal strategy to maximize both deliverability and reserves. Further technology improvements in water shut-off methods are being evaluated and may lead to deliverability and reserves enhancement if their effectiveness and reliability are proven.