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Block 23/16f and 23/21a (part) Columbus

Serica 50% (operator), Endeavour 25%, EOG 25%
Columbus Block Map

Columbus Area

  Pipeline

  Gas Condensate Field

  Oil Field

  Serica Blocks

Block 23/16f in the Central North Sea was awarded to Serica and its partners in 2005 in the 23rd Round of UK Offshore Licensing.  Block 23/21a (part), also known as ‘Columbus Sub Area’ was purchased by the 23/16f owners in October 2015. Serica’s partners in the blocks are Endeavour Energy UK Limited (25%) and EOG Resources United Kingdom Limited (25%).

In late 2006 Serica drilled the Columbus discovery well 23/16f-11 to a depth of 10,116 feet subsea and encountered a gross gas column of 125 feet in the Palaeocene Forties sands. The well was tested and, during the main five-hour flow period on a restricted choke of 56/64”, produced at a stabilised average rate of 17.5 mmscfd and 1,060 bpd of 47.5° API condensate with a wellhead pressure of 1,200 psi.

In 2007 well 23/16f-12 was drilled as a vertical appraisal well approximately three kilometres north of the Columbus discovery well, and encountered gas/condensate-bearing Palaeocene sands at a higher elevation than those tested in well 23/16f-11.  A full evaluation of the hydrocarbon-bearing interval was carried out and reservoir fluid samples were obtained.

To further evaluate the Columbus discovery, the 23/16f-12 well was then side-tracked (as 23/16f-12z) to a bottom-hole location approximately two kilometres north of the Columbus discovery well and encountered gas/condensate-bearing Palaeocene sands similar to those found in 23/16f-11.  Reservoir fluid samples were obtained and the well was suspended for potential use in the development of Columbus.

In December 2008, BG International ("BG") drilled an appraisal well (23/21-7x) in Block 23/21a (part), and proved the extension of the Columbus Field into the block.