Obtain HD images of vuggy, carbonate reservoir with high stick/slip potential

East Java Basin carbonate reservoir is known for being vuggy and having fracture networks with potential connections to an aquifer. Preventing early water breakthrough is crucial and requires HD images to identify potential heavy fracture densities, enabling optimal placement of isolation packers and spacing of ICDs to control reservoir fluid flow and mitigate exposure to the aquifer.

Saka Energi planned a horizontal well to increase penetration length of a productive interval within the reservoir. It would have a high deviation of 80°–90° inclination. Penetrating the vuggy and fractured carbonate reservoir not only presented a hazard for early water breakthrough but also a strong risk of mud loss, as experienced while drilling nearby offsets. Each offset required an additional, dedicated run with conventional high-angle wireline logging and an added potential for slick/slip.

Use MicroScope HD 475 service to acquire formation data while drilling

Schlumberger recommended combining MicroScope HD 475 service with VISION 475 LWD service and a PowerDrive X6 rotary steerable system. These components would acquire and transmit resistivity-based imaging in real time while drilling for quick fracture and geological feature evaluation. This would enable a quicker design for isolating the target area, using the density caliper from the VISION service and porosity information to design the ICD completion.

Optimized completion design requires accurate formation evaluation because the open fracture presence will boost permeability. Fracture identification and position determine ICD design and positioning. Consequently, higher definition borehole images are required for success.