EM-technology in ocean depths

Seismic exploration can be used to locate reservoirs in substrata, but cannot establish if these reservoirs contain oil/gas or water. However this is possible with the 10-year old EM-technology with which NGI researches intensively.

Since 1999 NGI has played a central role in establishing EM (Electromagnetic-technology) as a valuable resource. Prior to the use of EM, oil companies could apply seismic surveys to find reservoirs in geological structures but had to subsequently drill test wells down into reservoirs to confirm the findings of oil, gas or water. Such a well may cost NOK 150-200 million and it was not uncommon to drill ten wells before finding petroleum. Typically, an EM survey costs less than a tenth of a seismic survey and EM-technology has proved that test-drilling expenses are greatly reduced.

Surveying with marine EM-technology does not replace seismic surveys, but acts as a supplement providing more information about geological structures exposed by seismic surveying. NGI carries out ongoing research to combine these two areas, both in technology and in data analysis. Future technology will be used in oil extraction to monitor oil and water distribution in reservoirs.