Case Study: a large operating company eliminates unplanned drilling costs with SLB's IriSphere look-ahead-while-drilling service

Operator uses IriSphere service to accurately detect formation top 10 m ahead of the bit to pinpoint casing-set location

SLB worked with a large operating company in Sulawesi, Indonesia, that needed to drill an appraisal well to delineate a gas reef carbonate buildup but faced major uncertainty in locating the top of formation. Low-resolution seismic data, lack of correlation markers, and the risk of confusing thin limestone stringers with the target carbonate created a ±40 m margin of error and the possibility of setting casing too shallow, which could trigger an unplanned 6-in hole section and at least USD 1.35 million in extra cost.

SLB recommended its IriSphere look-ahead-while-drilling service to detect formation features in real time and identify the formation top before reaching it. The service distinguished stringers from the main carbonate, confirmed the true top of formation 176 m deeper than the initial assumption, and detected the target 10 m ahead of the bit, allowing 9⅝-in casing to be set at 1,706 m MD, about 4–5 m above the formation top. SLB’s solution avoided the unplanned 6-in hole section and enabled better coring, logging, and well testing for improved reservoir delineation and future field development.