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Seismic Data Processing and Quality Control

Danvic and her technical partner Spectrum Geo offers a wide range of modern data processing services to overcome seismic processing challenges for clients worldwide.

These services include:

• 3D and 2D Processing Solutions
• Land and Marine Processing
• Pre-Stack Migration in both Depth (PSDM) and Time (PSTM)
• Specialist Multiple Removal Techniques
• AVO and AVAZ Analysis
• Inversion Studies

Within the Danvic and Spectrum workforce, there exists experience of processing data from all parts of the world and proven success in handling difficult and challenging data sets - from refraction statics in the dunes of North Africa to PSDM in the Gulf of Mexico; from AVO offshore Nigeria to inversion in the North Sea. Our Geophysicists utilise a carefully selected combination of proprietary and third party techniques to achieve the ever-increasing technical demands of our Multinational clients. We use state-of-the-art, cutting-edge technology, frequently updated to deliver the very best possible results to our clients.

On-Board Processing

Since 2007, Spectrum ASA has provided on-board processing services for external clients as well as for our own Multi-Client surveys. This service Danvic/Spectrum is also making available to our clients in Nigeria. Currently, Spectrum charters one boat, the GGS Atlantic, which was recently completely refurbished and is now capable of acquiring and processing high quality long offset data anywhere in the world.

Spectrum on-board processing uses a Linux-based computer configuration very similar to our land-based processing systems. This arrangement allows for more efficient technical support and movement of equipment from vessel to vessel. It also enables quick and easy problem solving from onshore colleagues already familiar with similar systems.

A typical on-board configuration consists of a master server plus 52 processing nodes; each node with 2 dual processors. Spectrum’s proprietary software package, SPA, performs most of the processing on this system and was specially designed and developed for this multiple node computer set-up. In addition, there is a Sun workstation which runs interactive software packages for velocity analysis and other QC-related applications.

Onboard processing benefits the client in several ways:

• QC of acquired data in a timely fashion
• Involvement of Onboard client reps, start to finish
• Parameter selection is done quickly
• Fast turnaround of data processing

Currently all boats serviced by Spectrum's on-board processors are shooting 2D data but some will be acquiring 3D data in the near future. All of the boats have data processors working 24 hours, seven day per week on 5 or 6 week rotations. The geophysical crews are flexible and are tailored to each individual vessel/project. Onshore support is always available to help resolve any unforeseen software or hardware issues.

Each vessel has a Linux cluster computing system capable of performing onboard Pre-Stack Time Migration in addition to routine acquisition QC such as brute stacks, shot QC, near-trace QC and RMS analysis. Each system possesses plenty of computing power and storage space, along with RAID disks for added security.