The North Sea Zechstein play continues to attract interest from the industry, with Shell drilling the highly-anticipated Pensacola well in the UK Sector probably this year. Another example of progress made in terms of imaging the Hauptdolomit (Zechstein 2 Carbonates) along the southern margin of the Mid North Sea High is the extensive 3D survey acquired by ION last year.
Even though targeted licence applications, well commitments or 3D seismic survey acquisitions to further investigate the Zechstein play have not been seen in the Dutch sector to date, the complex of build-ups does extend eastwards from the UK. For that reason, TNO and Cambridge Carbonates performed and publicly released a study to better map and characterise the Hauptdolomit succession in the northern Dutch offshore around the Elbow Spit High (ESH on map below).
The reports in the form of two extensive powerpoint presentations can be found at the EBN website through this link.
We have updated our Mid North Sea High map with the newly mapped outlines of the Hauptdolomit platforms from this study. In comparison to what was mapped before, the extent of the platforms has decreased slightly, but a much better linkage between the location of the platforms and the transition from the structurally elevated areas to the Zechstein basins has been achieved.
Along the southern margin of the Mid North Sea High, the platforms could be mapped with most confidence in an area that shows a gradual transition from proximal to basinal facies. This is the area where well E02-02 was drilled. The northeastern margin is characterised by a much more rapid transition from platform to basinal facies, which may have prevented the formation of build ups to the same extent as seen in the south. However, a line of tentative build-ups has been interpreted in this area where only 2D seismic is available.
In the far north of the Dutch offshore, mapping of the Zechstein build-ups proved to be more challenging due to lack of data and the outlines in this area should therefore taken with caution.
It will be interesting to see if there will be a ramp up in interest in this region now that the outlines of potential drilling targets have been mapped in greater detail. A positive result at Pensacola will surely help.
HENK KOMBRINK
