Providence excited about Dunquin South prospect, as seismic data arrives

Irish oil and gas explorer Providence Resources is excited about the seismic survey results at the FEL 3/04 license offshore Ireland.

The offshore block, operated by Eni,   lies in the southern Porcupine Basin, c. 200 km off the south-west coast and in c. 1,500 m water depth.

It holds the undrilled Lower Cretaceous “Dunquin South” carbonate exploration prospect as well as the “Dunquin North” residual oil accumulation. Apart from Eni and Providence, other partners in the block are Sosina, and Repsol.

In a statement on Friday, Providence said that the partnership had received the recently acquired Dunquin 3D seismic data and an initial interpretation had been completed.

Providence said that the interpretation had confirmed the presence of the previously mapped Dunquin South prospect.

“In addition, a large and significant potential fluid escape feature is evident over the previously drilled Dunquin North prospect. No such feature is evident over the Dunquin South prospect. Imaging of the underlying c. 700 km2 Dunquin Ridge has also been greatly enhanced and the internal reflectivity, in tandem with the seismic interval velocities, indicate the ridge to be of sedimentary origin,” Providence said.

No chimney over Dunquin South

Providence said that the interpretation had confirmed the presence of the previously mapped Dunquin South prospect.

John O’Sullivan, Technical Director of Providence said: “The new 3D seismic data over FEL 3/04 are greatly enhancing our understanding of the exciting exploration potential of this block. The presence of a major chimney over Dunquin North has been identified as the main reason for prospect failure. It is obviously highly encouraging that no such feature has been identified over Dunquin South, which we believe substantially de-risks this exciting exploration prospect.

In addition, the data are suggesting a sedimentary versus volcanic origin for the erstwhile enigmatic Dunquin Ridge, which itself may provide another very significant stacked exploration target for a future Dunquin South well.”

The Dunquin North well was drilled in 2013 by then operator ExxonMobil. Preliminary well analysis indicated the reservoir to be water bearing, however, Providence said the petrophysical log interpretation, elevated gas levels, together with oil shows in sidewall cores over the upper section of the reservoir, suggested the presence of a residual oil column.

In 2014, the results of the post well analysis from the Dunquin North exploration well were announced which confirmed that the prospect contained at least a c. 44m residual oil column in a thick, over-pressured, high porosity carbonate reservoir system that was breached, with pre-breach oil STOIIP volumetrics of c. 1.2 BBOE, and with a current estimated residual oil STOIIP of c. 600 MMBO.

In a further update, Providence said a re-analysis of the 44/23-1 Dunquin North well data suggested that the original hydrocarbon column may have been significantly greater than the previously reported 44m and may have covered the entire 250m drilled interval, which may have significant implications for the Dunquin South prospect and the underlying Dunquin Ridge.

In its update on Friday, Providence did not provide any estimate on when and if the Dunquin South well would be drilled.