Effect of Zechstein Supergroup (Z1 Cycle) Werrahalit Pods on Prospectivity in the Southern North Sea

Results of a seismic interpretation and the analysis of exploration wells in license blocks in the southern part of Southern North Sea (SNS) Quadrant 49 highlight the presence of poorly documented, lensoid Werrahalit pods within the lowermost of the Upper Permian, Zechstein Supergroup (Z1) carbonate-evaporite cycles. Their occurrence has a demonstrable effect on the accurate definition of structural traps and reserve estimates in the highly prospective Leman Sandstone Formation reservoir underneath. There remains a clear need for the zone in which the pods occur to be delimited and the effect of the Werrahalit to be accounted for when evaluating remaining prospectivity in the SNS in order to assess the exploration and production risks and rewards that their presence brings.