Case Study of Low Resisvity and Mrginal Reservoir Development in Echo Field

Abstract

Echo field is one of major oil contributor in Offshore North West Java area. The field starts its first commercial oil in 1971 and peak its production at 54,000 bopd in 1973. As the field gets mature over time, the hydrocarbon production also declining. Current production of the field is 8,000 bopd and 8 mmscfd. Water injection was applied in early 2002 and provides significant reserves addition. Further field development strategy is required to sustain hydrocarbon production and maximize recovery of the Echo field. The strategies that have been executed are focusing on development of low resistivity reservoir, marginal reservoir, and by-passed zone.

Over the last couple of decades, low resistivity pay in Echo field were considered less attractive and sometime interpreted as non-reservoir. Integrated subsurface evaluation and the application of suitable hydraulic fracturing technique prove that the low resistivity reservoir in Echo field provide quite significant addition to production and reserves. The peak production from the low resistivity zone is around 3,000 bopd.

The same integrated subsurface evaluation was also applied for the marginal reservoir, both oil and gas reservoir. The development of the reservoir was mostly done by workover to minimize investment cost and optimize cash flow. The development of this marginal reservoir is considered a success with well production between 100-200 bopd and 2 mmscfd. Production from by-passed zones also plays an important role in the Echo field development. The by-passed hydrocarbon was identified either from infill well result or data acquisition such as production log and saturation log. These by-passed zones were mostly produced through well services job such as squeeze & perfo, water shut-off, zone change and well recompletion or well reactivation.

The paper will discuss the success story and lesson learnt of the Echo field development, especially the low resistivity and marginal reservoir, and the future development plan.