Paper Summary

We describe a series of barnacle mitigation measures applied during a five-month towed-streamer seismic survey by the Ramform Titan in the Campos Basin, Brazil. The 14 x 10000m streamer spread was an industry record and occurred during the period of the year recognized as the high season for barnacles in the area, and was frequently affected by challenging weather too. The high-capacity seismic vessel was equipped with a pilot system for coating streamers with a proprietary anti-barnacle coating, deployed the self-propelled streamer cleaning units common to all PGS operations, and was also supported by the Thor Frigg; a large support vessel (Figure 1) equipped with a proprietary fast-going underwater drone capable of deploying the self-propelled streamer cleaners without workboat operations. Collectively, these barnacle-mitigation efforts present a unique insight into the complementary solutions necessary for remote operations in the most challenging settings. Our experiences demonstrated the usefulness of those tools. The prototype anti-barnacle coating required no attention for eight weeks on the streamer fronts where barnacle growth can become problematic during periods of no workboat activity being possible. The underwater drone removed the weather factor that correspondingly limits barnacle cleaning with traditional workboat-based tools, and thereby prevented a full spread recovery. The collective anti-barnacle mitigations enabled the survey to be completed ahead of schedule, despite particularly challenging conditions. Workboat-related HSE exposure was also greatly reduced.