Blocks 28/9 and 28/10c are traditional licence awards. They lie on the western margins of the Central Graben. Both blocks had previously been licensed but were undrilled.
The blocks contain a number of Eocene and Forties age structural and stratigraphic closures, and two large Jurassic leads. The main prospect was Catcher, a structural trap with an observed direct hydrocarbon indicator. A significant light oil discovery was made at Catcher in June 2010.
The work programme for the block included reprocessing of 3D seismic data and a firm well to test the Catcher prospect. A seabed survey was completed to confirm that the well could be drilled using a heavy duty jack-up rig. The Transocean Galaxy II heavy duty jack-up rig began drilling the well (28/09-1) in May 2010 and resulted in a significant light oil discovery annnounced on 3 June 2010. The well established a minimum 240ft oil column with a calculated net pay of 90ft.
A mechanical restriction in the test string meant that it was not possible to flow the well in a stabilised manner through the separator during testing. However, EnCore and its co-venturers decided that samples gathered and well deliverability estimates provided the necessary information required to undertake development studies. The co-venturers then drilled a side-track well to Catcher East which resulted in an oil discovery announced on 28 June 2010. The side-track well (28/09-1Z) indicated 82ft of net hydrocarbon pay over a gross interval of over 236ft and initial analysis of the data indicated that both Catcher East and Catcher are likely to be part of a single significant oil accumulation. EnCore and its co-venturers then appraised the Catcher South West (28/09-1Y) which again successfully encountered excellent quality oil bearing reservoir sandstones at the target Cromarty Sandstone level.
Commenting on Catcher, Alan Booth, EnCore's Chief Executive Officer has said that "initial analysis of the seismic data, now calibrated by drilling, suggests that block 28/9 could possibly contain a series of discoveries that would form one of the larger North Sea oil accumulations of recent years. EnCore’s initial scoping analysis indicates that the Catcher feature (including East and North) may contain Oil in Place of up to 300 mmbbls. Further work will be needed to determine likely recovery rates".
The current phase of the Catcher area drilling programme is now complete and the Galaxy II rig will be released following completion of the 28/9-1Y well operations. In the meantime, EnCore and its co-venturers are preparing to acquire a number of new site surveys, starting in July 2010, over additional potential drilling locations in Block 28/9. The group is also in discussions to secure a rig for a further exploration and appraisal drilling programme for the Catcher area. It is possible, though at this time uncertain, that further drilling may recommence as soon as autumn 2010. Further announcements will be made as appropriate on the likely timing of future drilling activity.
EnCore has a 15 per cent. equity interest in the blocks and is Operator. EnCore's costs of the initial Catcher well were carried by partners Premier Oil (uncapped) and Wintershall (capped). It is expected that the cost to EnCore of the May - Jul 2010 Catcher drilling campaign will not make a material impact on the Company’s cash resources.
The equity in the Catcher joint venture partnership is as follows: EnCore Oil plc (15 per cent., Operator), Premier Oil (35 per cent.), Wintershall (UK North Sea) Limited (20 per cent.), Nautical Petroleum (15 per cent.) and Agora Oil & Gas (15 per cent.).
