The East Belumut Field

East Belumut was discovered by an International Oil Company (IOC) in 1970 with an additional three appraisal wells drilled in the 1990’s. The IOC deemed the field to be non - commercial due to a thin oil column and a viscous crude oil resulting in a low recovery factor (< 10%). They relinquished their acreage to the NOC who also considered the field too difficult to develop.

In June 2005 Newfield (now Sapura E&P) signed up to develop the Field with an aggressive development and exploration bid that won the PM323 Block. For Sapura E&P, East Belumut was an opportunity to apply modern horizontal drilling, innovative completion technology and state of the art geological modelling and reservoir simulation to significantly increase the oil recovery from the field. Initially the IOC/NOC expected the East Belumut Field to recover < 10% of its oil in place and produce around 20 MMBO. However, today Sapura E&P has more than tripled the recover to > 65 MMBO. This has been achieved through application of cutting edge technology, innovation and phased learning.

A Uniquely Challenging Project

Subsurface challenges posed to the development team included a low-relief structure, a thin-oil column just 15m wide, a high-permeability clastic reservoir with an overlying large-gas cap and underlying strong-water aquifer. Surface challenges included constructing and installing a platform in time for the First Oil deadline within 3 years. This included the tie-in of the main export line via older facilities flowing through Tinggi (PM9), Tapis (ExxonMobil) and on to TCOT (Carigali).

Innovative Completion Techniques

Successful application of technologies to the development of the East Belumut field resulted in better production performance than originally predicted in the Field Development Plan.

A phased development-drilling approach was adopted to be able to react to geology and reservoir production learnings. The static-geology and dynamic flow-simulation models have been updated between these phases, which has led to optimisation of the horizontal well landing-depth, length, spacing, and well count for optimal production and reserves.

All of the horizontal wells are completed with Inflow Control Devices to distribute the reservoir pressure drawdown evenly along the entire wellbore length. Production Logging Tools and tracer technologies have been applied to confirm the entire horizontal section contributes to the total fluid flow.

High Safety & Production Consistency Over 7 Years

The East Belumut Central Production and Processing Platform-A has been constantly upgraded to cater for better than expected field performance. Platform upgrades have included bigger compressors to replace the start-up rental units. Higher crude export capacity was obtained by the installation of a much larger Free Water Knock-out vessel (separator) to increase total fluid handling and upgrades to the produced water system to increase water handling.

The platform has been operating with no spare capacity and maintaining a 98% uptime record, and the seven years of production since first oil in July 2008 shows East Belumut has consistently exceeded expectations. Continued infill drilling programmes have seen production rates maintained, with field oil ultimate recovery is significantly enhanced to triple that expected. The HSE record of the platforms has been good with only a couple of recordable incidents (first aid treatment) on the platform and twice in its history exceeding a million man hours without a recordable incident.