08-10-09 Gas has been discovered in the Tiendeveen-1 exploration well in the Drenthe III license.
Tiendeveen is sited in the east of the Netherlands, 3.8 km northwest of Northern Petroleum's Geesbrug gas field development. The gas in the Permian Zechstein carbonates which had been identified as a secondary target in the well has been confirmed from wireline logs and drilling data.

The Geesbrug gas field which Northern Petroleum is developing nearby is also gas bearing in the same Zechstein reservoir. Northern Petroleum will review both the Tiendeveen and Geesbrug data to assess the range of possible reserves, development options and synergies.
No potential gas-in-place volumes were assigned to the Zechstein prior to drilling.

The intermediate casing will now be run in the hole cemented and pressure tested before the drilling deeper to the primary reservoir targets located in the Permian Rotliegend sandstone and the Carboniferous Dalen and Hardenberg sandstones. The estimated mean potential gasin place for these reservoirs is 60 bn cf with an upside P10 potential of 98 bn cf.
Once drilling has been completed further wireline logging will be undertaken on Tiendeveen to confirm the presence of hydrocarbons in the deeper primary targets.

Partners in the well are Northern Petroleum Nederland (NPN is a wholly owned subsidiary of Northern) with 45 %, EBN, the state oil company and Dyas with 40 % and 15 % respectively.