Druid Prospect, Southern Porcupine Basin

Druid prospect lies in the Frontier Exploration Licence (FEL) 2/14 of the Southern Porcupine Basin offshore Ireland in water depths of approximately 2,250m.

FEL 2/14 is jointly owned by Providence Resources (80%) and Sosina Exploration (20%), with the former serving as the operator. The joint venture (JV) is currently exploring the Druid prospect and planning to drill an exploration well in June 2017.

A farm out process for the prospect was also initiated by the JV partners in March 2016 to select a suitable partner to develop the oil field.

Druid prospect geology and reserves

The Druid prospect contains two fans located at a depth of 1,750m below the mud line (BML). The two fans include potential fluid escape from the pre-Cretaceous Diablo Ridge.

Seismic and rock physics analysis indicates that the Druid prospect features an 85m-thick, highly porous sandstone reservoir containing light oil. Geo-mechanical analysis has further indicated the Druid prospect to be normally pressured with its top seal intact.

The cumulative resource potential of the prospect is estimated to be 3.18 billion barrels of oil (BBO), with Fan 1 containing 984 million barrels of oil (MMBO) and Fan 2 containing 2,196MMBO.

Druid prospect exploration

Following the award of the FEL 2/14 license in October 2011, the developers discovered two large vertically stacked Paleocene and Lower Cretaceous fan systems through available 2D seismic data.

The Paleocene fan system was named as the Druid prospect, while the lower Cretaceous fan system was named Dromberg.

The JV later licensed a 3D seismic survey acquired by Polarcus in 2014 and, after processing the 3D data, collaborated with Schlumberger to explore the southern Porcupine and Goban Spur Basins. The team worked together to confirm the regional resource potential.

In April 2016, the resource potential of both Druid and Dromberg was confirmed with the collective prospective resources estimated at 5,095BBO.

The JV announced the planned drilling programme for the Druid prospect in August 2016. Stena IceMAX drill-ship will be used to drill the 53/6-A exploration well to 4,200m true vertical depth subsea. The well cost was originally estimated at $46m but later reduced to $35m.

The well will enable the developers to fully assess the resource potential of the Druid prospect. It will be designed for potential deepening to explore the underlying Dromberg prospect.

Details of the Stena IceMAX drilling rig

The Stena IceMAX is a dynamically positioned, dual derrick ice-class drilling rig capable of operating in water depths of 10,000ft. It is 228m-long, 42m-wide, and has an operating draft of 12m.

Drill control equipment of the ship include two blowout preventer (BOP) stacks including a 18.75in x 15psi Cameron TL BOP, Cameron Load King riser, two Cameron DL Annular, a GE Vetco wellhead connector and a GE Vetco diverter. It is equipped with dual hosting and drilling tower and a helideck designed for EH-101 and S-92.

Drillwater capacity of the ship is 4,350m³, fuel oil capacity is 16,565m³ and bulk oil and brine capacity is 490m³.

Contractors involved

The developers have appointed Senergy Wells to manage the drilling programme for the prospect. Senergy’s scope of work includes design, engineering, construction and management of the exploration well.

Providence signed a contract with Stena Drillmax Ice in November 2016 to provide the Stena IceMAX drill-ship for the drilling programme. The contract is for the drilling of one firm well and includes an option to drill a follow-on well.

ION Geophysical processed the 3D data acquired for the prospect.