Insights to Reservoir Architecture Through Multi-Penetration Pilot (MPP) Wells

Tangen, Odd, Kjell Espejord, ExxonMobil, Norway

Abstract: The Ringhorne development in the Norwegian part of North Sea is an extend­ed reach development with 24 wells planned within an 8 km radius of the platform surface location. The platform is designed to drill to 7 accumulations with target TVD ranging from 1750 m to 2000 m. Challenges for this development include locating thin sands far from the platform and optimally placing long and complex horizontal producers into those sands.

The initial geological model of the Upper Paleocene Forseti reservoir included 5 to 10 meter thick sheet sands based on three exploration wells, as the existing seismic was unable to define the exact location and thickness of the reservoir. Due to the planned lengths of the horizontal producers, several conventional pilots would have been required to properly eval­uate the boundaries of the formation and subsequently place the horizontal producer. New and better quality seismic available pre-drill, suggested a depositional model consisting of compensational stacking of different age sand bodies rather than a sheet sand. The concept of Multi Penetration Pilot (MPP) was used to increase the number of reservoir penetrations. By drilling an undulating pilot multiple times through the top and bottom of the reservoir with LWD, sand mapping would be substantially improved and thereby reducing the geolog­ic risk when determining the specific location of the horizontal section of the producers.

The Multi Penetration Pilot (MPP) wells achieved it’s primary purpose of assisting with locating the tops and bottoms of the reservoir section over more than 1000m MD. In addi­tion, this concept has saved conventional pilot hole sidetracks.