CSEM De-risking Potential Demonstrated by Recent Well Results

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.