Investigation of new play models will always imply increased risk, as there are no documented calibration points (wells). The main uncertainties will be connected to the presence of potential reservoir deposits and a working hydrocarbon (HC) system which can charge the reservoirs with hydrocarbons. CSEM data has the potential of greatly reducing these uncertainties, as high-quality reservoirs saturated with HC are associated with anomalously high resistivity. In contrast, the lack of resistivity reduces the chance of making commercial discoveries.

This can be illustrated with an example from Norway, in the Barents Sea. Seismic data indicated two fluid contacts (GOC & OWC) on a new Tertiary play in the area. This buoyed interest for a large aerial extent of the prospect. Unfortunately, CSEM data showed high resistivity only on the upper part of the gas area, and no resistivity in the anticipated oil leg. This observation motivated some oil companies not to apply for the block (gas-only with too small volumes). An explorer eventually drilled the assumed GOC, found the gas leg above, but only water underneath. The discovery was declared non-commercial.

Despite the disappointing result, CSEM data supported the new Tertiary play type, and helped to increase the PoS of this new play type.

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