Marine CSEM Technology—The Luva Case

In 2003, the Norwegian company emgs collected controlledsource electromagnetic (CSEM) data over the offshore Luva gas discovery in the Norwegian Sea. The purpose was to test the technology above a proven discovery. However, the response from the gas-filled reservoir was very weak and the example has been used to argue the limitations of the technology. The low CSEM response is a result of resisitivity anisotropy in the reservoir section, which causes a weak contrast between the target and the surrounding rocks. However, by applying an advanced integrated approach, it is possible to resolve the CSEM anomaly associated with the gas discovery. The case study clearly demonstrates the potential of CSEM technology for exploration purposes. The example also illustrates the complexity associated with the processing of such data.

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