A Marine Vibrator 3D Acquisition and Processing story

SUMMARY

In 2023, a first 3D survey using towed marine vibrators (MVs) was conducted over the Johan Sverdrup field in the North Sea. The survey, employing both low-band and high-band units, covered a broadband seismic frequency range from 3 to 150 Hz.

The incorporation of phase encoding effectively minimized residual sweep noise, eliminating the need for silent breaks between sweeps and achieving nearly 100% utilization. An additional test confirmed robust low frequency signal emissions in the 2-8 Hz range, which is useful for Full Waveform Inversion (FWI) and imaging.

This survey was also the first time the entire acquisition system was tested, including towing, handling, positioning, control software, source signature measurements, and Quality Control (QC). The dataset collected in this survey proved valuable for processing and imaging tests.

Processed MV data compared well with legacy airgun-based data, highlighting the potential of employing marine vibrators for large-scale broadband seismic surveys in both 3D and 4D settings.