In the marine environment, geophysicists can acquire seismic data using two fundamentally different methods. The first involves streamer cables that are towed by vessels on the ocean’s surface. The hydrophones within the streamers are able to acquire pressure (P-wave) data only, because shear (S-waves) cannot travel through fluids like the water column in the ocean.
If geophysicists want to obtain full-wave (multicomponent) seismic data, including shear waves, they must utilize the second acquisition method that involves putting the seismic sensors directly on the ocean bottom. ION has developed a redeployable acquisition system called VectorSeis Ocean (VSO) to enable full-wave data to be recorded from the seabed.
VSO integrates several proprietary ION technologies including VectorSeis digital full-wave sensors, a buoyed recorder, and a patented noise-reducing cable system. VSO is purpose-built to ensure high fidelity recording of the full seismic wavefield from the low noise environment of the ocean bottom. At the core of VSO is VectorSeis, the company’s award-winning, full-wave sensor. VectorSeis captures broadband seismic data with the highest vector fidelity available in the marketplace. The results are high resolution images of the reservoir, even for deep targets. Specific applications of full-wave seabed imaging include:
- Imaging thin, stratified, highly-faulted, or steeply-dipping reservoirs
- Delineating lithology (rock type) changes
- Determining fluid types and fluid movements, especially in 4D programs
- Acquiring seismic data in the presence of infrastructure obstructions
- Imaging through gas clouds
- Delivering low frequency data (down to 1-2 HZ) for AVO and inversion
The dream of every asset manager is to be able to cost-effectively track fluid movements within a reservoir on a real-time basis. ION’s VectorSeis Subsea Network (VSSN) is an emerging technology that promises to make the dream of permanent reservoir monitoring a reality. After investing in VSSN, an asset manager will be able to obtain frequent, accurate, low-cost 4D images of fluid movement and distribution within the reservoir. This will enable:
- More efficient stewardship of the asset
- Improved cash flow
- Increased total recovery
- Reduced risk
ION has been a forerunner in permanent reservoir monitoring. The company was involved in designing the technology used in the early seabed 4D experiments at Teal South in 1996 and, through its Concept Systems subsidiary, provided data integration and QC systems for the Valhall Life of Field Seismic project. More recently, ION has forged a partnership with subsea specialist Vetco to expand the range of applicable acquisition technologies and deployment techniques available for permanent reservoir monitoring projects.
For both redeployable and permanent seabed acquisition systems, ION offers a comprehensive suite of technologies and services that span the entire seismic workflow, including:
