In 2011, six wells were drilled in locations where CSEM data existed. Two of these were discoveries while the remaining four were dry. This provides a discovery rate of 33%. Three wells were located in a position with significant CSEM response (normalized anomalous response, NAR, above 15% for the fundamental frequency). The discovery rate for those wells was 67% (2 discoveries). Three wells were located in positions without a significant CSEM response (NAR below 15% for the fundamental frequency) and all three wells were dry, providing a discovery rate of 0%. The well results thus provide supporting evidence for the CSEM technology as an important de-risking tool. In fact, using the cut-off value of 15% to separate between clear CSEM anomalies and no or weak CSEM anomalies, as many as five of the six (83%) wells are in accordance with the observed statistics with 2 true positives and 3 true negatives. Only 1 false positive is observed according to this definition. For exploration on the Norwegian Continental Shelf, it is of interest to observe that 4 of the 5 largest discoveries over the past decade have been mapped with positive CSEM responses. These are Skrugard, Havis, Norvarg and Goliat.


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