Wide-azimuth seismic surveying using seabed recording has been performed for many years but the full potential is only now being recognized.

Seabed surveys have been mainly used for specific geologic problems such as imaging through gas clouds using converted waves, as a solution to operational problems such as proximity to production platforms, or for imaging deepwater complex sub-salt structures. Additionally, life-of-field surveys use permanent installations to optimize receiver repeatability, improve sensor coupling and for economic reasons.

Now, the advent of towed-streamer wide-azimuth surveys has highlighted other benefits such as illumination, noise and multiple suppression and fracture characterization. Seabed operations can add value by combining the benefits of wide-azimuth geometries and multi-component recording.

CGGVeritas offers both multi-component OBC and OBS solutions and has a wide experience of applying these technologies for its clients worldwide.

Retrievable OBC operations using a specialized cable deployment/handling vessel (pictured) and a portable, containerized omni-directional source (shown being towed)

Features:

• Integrated solutions from comprehensive feasibility studies to seabed acquisition and multi-component processing
• Multi-component OBS nodes and retrievable OBC cable
  • Advanced retrievable SeaRay cable with MEMS 4-C digital sensors operational to 300m
  • 4C OYO Geospace cable for depths up to 3000m
• Specialized cable deployment/handling and dedicated source equipment
• Permanent reservoir monitoring solutions for life-of-field studies using the state-of-the-art Sercel Optowave fibre-optic cable
• Worldwide seabed experience
• QHSE excellence

Benefits:

• Facilitates dense source grid wide-azimuth acquisition
• Combines wide-azimuth and multi-component seismic benefits
• Superior and uniform illumination and sampling in obstructed areas

The Optowave life-of-field installation planned for Ekofisk for 2010 will be the largest permanent monitoring system installed to date, covering 60 sq km and consisting of 4000 4C channels.