• What is EM imaging?
• How does EM imaging work?
• Technology components
  • Receivers
  • Source
  • Processing & Modelling
  • Survey vessels

Source

A powerful EM source is required to illuminate deep targets. Being able to control the source signature enables EM imaging surveys to be customised for maximum response.

For processing of EM imaging data, the location of the source must be accurately known and the timing of the received EM fields must be synchronised with the source signature.

Successful surveys rely on powerful controllable sources that can operate continuously and reliably for very long periods and without impact on the marine environment.

Main Features

• 1250-A peak output strength. The EMGS source has the power to transmit energy deep into the subsurface.
• Positioning and custom-designed navigation software. Advanced positioning systems developed for the ROV industry are supplied to EMGS by industry leaders Kongsberg and Sonardyne. Concept Systems has developed navigation software for EMGS' use based on GATOR™.
• Synchronisation. The transmitted signals are synchronised with the received signals using GPS time-reference signals backed up by accurate onboard clocks.
• Environment. Independent studies have demonstrated that the EMGS EM source is not harmful to marine life, even though it is sufficiently powerful to penetrate over 3000 m of rock.

• Reliability. The EMGS source is custom-manufactured by Siemens to EMGS' design. The design is based on knowledge gained from continuous improvements during four years of operation.
• Frequency variation from 0.05 to 10.00 Hz. The source signal is optimised for each survey by specifying the frequency components and corresponding amplitudes. This significantly improves survey results.