Tullow Oil plc (Tullow) announces that the Jupiter-1 exploration well in Block SL-07B-11 offshore Sierra Leone has successfully encountered hydrocarbons. This has been confirmed by the results of drilling, wireline logs and samples of reservoir fluids.

The well, located over 25 kilometres west of the Mercury-1 well which discovered oil in the block, intersected 30 metres of hydrocarbon pay in the primary Upper Cretaceousobjective and did not encounter a hydrocarbon water contact. The well has been preserved for possible future re-entry, as the area is likely to require additional evaluation.

Jupiter-1 was drilled by the Transocean Discoverer Spirit drillship to a total depth of 6,465 metres in a water depth of 2,199 metres. On completion of operations, the drillship will move 15km northeast to the Mercury-2 well which will target several reservoir levels including extensions of the oil accumulations discovered by the Mercury-1 well.

Anadarko (55%) is Operator of offshore Block SL-07B-11 along with partners Repsol (25%) and Tullow (20%).