Publications

The West Seno Field is located in deepwater offshore East Kalimantan, Indonesia. The field was discovered in August 1998 and was delineated by 13 appraisal wells. Development drilling began in March 2003 and concluded in December 2004. Twenty-eight development wells were drilled from a 28-slot dry tree tension leg platform. Ten of the wells were horizontal wells completed with ~ 1000ft Wire-Wrap Screen (WWS) completions placed in the larger reservoir sands and 18 deviated wells were positioned to develop smaller and stacked channel sands through cased hole perforation and frac-pack completions. Field production was started in August 5, 2003 and initiated the first deepwater production within the Republic of Indonesia. West Seno is a complex field comprising ~50 independent compartmentalized hydrocarbon bearing reservoir sand equilibrium regions. Reservoir fluids vary by sand from dry gas, to saturated and under saturated oil. Many sands do not have a GOC and or OWC penetrated by a well, and consequently volume of in-place HC is uncertain. The development is further challenged by the unconsolidated nature of the reservoir sand and the need of sand control in order to sustain production. There are also a number of additional flow assurance concerns relating to carboxylic acid soap emulsions, wax and hydrates. The current subsurface development strategy has evolved from the original POD concept involving a 2 TLP development to the recently (August 2008) revised and optimized development plan of a single TLP development with a second phase of development drilling. A combined Extended Reach Drill (ERD) well and Conventional Reach Drill (CRD) well development drilling campaign are planned for year 2010 to supplement the existing development. It will also utilize slots from abandoned wells on the existing TLP. Reservoir management of the current development is based upon a bottom up, plug back and complete strategy. A rigorous reservoir surveillance plan involving regular FBHP surveys in most wells allows for for material balance calibration of reservoir simulation models that have been constructed for the larger reservoir units. Development plan optimization is conducted continuously throughout the development of West Seno with monthly update to production forecasts, reserves, and well workover schedule. Well workovers are campaigned to provide cost effective recompletion using wireline, coil tubing and a hydraulic workover snubbing unit. In addition, day to day production is optimized through the management of produced sand, gas lift optimization, water cut and GOR control.