Apr 23, 2013 - Premier Oil is finishing up a successful exploratory drilling campaign at its 50%-owned Bonneville prospect in the UK North Sea. Well 28/9a-6 and its sidetrack, 28/9a-6z, were drilled by the WilPhoenix (mid-water semisub) to 4,481 and 4,441 feet respectively. Both wells encountered high quality oil-bearing reservoir rock in the Tay interval with average porosities of approximately 30%. Fluid samples indicate 25 degree API oil which makes it similar to the nearby Burgman discovery. Once final activities are complete at Bonneville the WilPhoenix will mobilize to the Premier-operated Solan field to begin development drilling.