Achieving Desired Fracture Placement in a Thick and Stratified Reservoir

Jaboob, M. (BP Oman) | Turk, G.A. (BP Oman) | Rylance, M. (BP Exploration) | Trejo, R. (Schlumberger) | Al-Shueili, A. (BP Oman) | Al Manji, A. (BP Oman) | Ishteiwy, O.A. (BP Oman)


The Barik formation is a low-permeability conventional tight-gas reservoir, in Block 61 in the Sultanate of Oman, comprised of a series of interbedded sandstone and mudstone (shale) layers. Such an approach was developed and deployed during the Appraisal stage of the programme and a considerable effort was placed in ensuring that the fracture height was contiguous, resulting in an effective drainage across all layers of the Barik formation. This approach was then encapsulated in the Full Field Development (FFD) planning Basis of Design (BoD) and was established as the approach to be taken throughout FFD. Until the field development was well underway, a single fracture treatment had proven sufficient to stimulate the entire Barik reservoir. However, as the development moved into the Southern area of the field, a substantial thickening of the Barik sequence was encountered and with this change successful complete vertical propped fracture coverage became much more challenging to achieve in an effective and repeatable manner.