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Mubadala Energy drilled three vertical wells in the offshore Andaman field, deepwater Indonesia, using a unique integration of logging while drilling (LWD) and wireline fiber-optic seismic technology. The primary objectives of this integrated acquisition were to reduce drilling risks, enhance safety during reservoir exploration, and significantly improve the cost-efficiency of deepwater well operations, providing a safer working environment for all involved.

Seismic While Drilling (SWD) technology was deployed in the 12¼-in hole section to assist with geostopping and ensure that the 9 ⅝-in casing was set just above the top of the Oligocene Bampo 26Ma clastic reservoir. The drilling continued on the 8 ½-in hole section to Total Depth (TD), with SWD data being rerecorded for comparison with wireline (WL) borehole seismic data. A new first-break picking method was used in one of the wells for velocity profile computation, followed by depth prediction using the look-ahead method. The 'look-ahead' method, a cutting-edge feature of SWD, allows for real-time prediction based on seismic data, enhancing prediction accuracy and reducing drilling risks. The proximity of the seismic sensor to the SWD tool further enhanced prediction accuracy, achieving depth uncertainties of ± 10 to 18 m from the target. Fiber-optic seismic technology further improved operational efficiency by reducing operational rig time. This technology provides a comprehensive end-to-end workflow, from planning and execution to processing workflow. Embedded with WL logging tools, the fiber-optic seismic technology eliminated the need for dedicated borehole seismic acquisition, completing seismic data recording in 1–2 hours. With a spatial resolution of 5 m and high-frequency data up to 80 Hz, it helps to delineate the reservoir zone in the seismic well-tie correlation process.

In conclusion, SWD technology played a key role in geostopping, and fiber-optic seismic technology effectively managed depth uncertainty and enhanced seismic well tie with improved vertical resolution. The advantage of utilizing both technologies is comparing and cross-validating the data, and in terms of operation, integrating SWD and fiber-optic seismic reduced operational risk and enhanced operation efficiency. This offers an innovative approach for borehole seismic acquisition in the deepwater environment in Indonesia.