Premier Oil’s “high-impact, play-opening” Isobel Deep North Falkland Basin well has made an oil discovery, the operator confirmed this morning, in higher than expected reservoir pressure.
Operations have been suspended and the rig will be released to drill in the South Falkland Basin, before returning to potentially re-drill on Isobel Deep or drill a side track.
The 14/20-1 well, drilled to 8289ft deep, short of planned total depth, hit 75ft of oil bearing F3 (Isobel Deep) sands, at high pressure, which resulted in an influx into the well. Oil recovered during operations to remove the influx was identified as similar to that in the commercial Sea Lion discovery, 30km to the north. Last week, Premier said it would run a casing string through a shale section above the “suspected elevated formation pressure” area, before continuing to drill before aiming for the target formation. It said then that there was a presence of oil shows, but that this was not necessarily indicative of net pay.
According to partner Rockhopper Exploration, the well, drilling using the Eirik Raude semisubmersible drilling rig, penetrated about one third of the mapped sand thickness at the location.
Premier Oil says it is now considering the optimal appraisal program for the Elaine/Isobel complex in PL004. The Isobel/Elaine complex is estimated to contain mid case un-risked gross prospective resources, based on the operator’s estimates, of 243 MMbbl, partner Falklands Oil and Gas said.
FirstEnergy Global Research said: We view this result as important for the Northern Basin. Isobel is a play opener in an unexplored area of the basin. While the well itself was targeting only 56 MMbbl P50 Prospective resources, it is part of the much larger Elaine/Isobel complex of 240 MMbbl Prospective Resources that is now partially derisked."
Isobel Deep, in exploration license PL004a, is Premier’s second exploration well in its 2015 campaign offshore the Falkland Islands, following a successful well on the Zebedee prospect.
The well is part of an overall five to six well exploration campaign in the Falklands by Premier and Noble Energy under a rig sharing agreement.
Andrew Lodge, exploration director commented: “This is an important play-opening discovery in the previously unexplored southern area of License PL004. The well has successfully demonstrated a trapping mechanism and the presence of moveable oil in the Elaine/Isobel fan complex.”
Sam Moody, CEO, said the find “significantly de-risks the entire Isobel / Elaine fan complex.” “Although the Well has not yet reached Total Depth the signs for the Isobel/Elaine complex so far are very encouraging and we will decide the next actions in appraising the discovery over the coming weeks while the rig is drilling to the south of the Falkland Islands."
Tim Bushell, CEO of partner Falkland Oil and Gas said: "Further operations on the well will be performed when the rig returns to the North Falkland Basin after the Humpback well. These could include either a side-track from the existing well or a re-drill of the well near to the current location, depending on what is deemed appropriate once the drilling results have been further evaluated."