There has been a tendency for years to write off Ireland as a serious player on the North West Europe Continental Shelf (NWECS).
This is perhaps understandable given that there has so far only been one commercial producer . . . the Kinsale gasfield, which has finally reached the end of the road.
There is of course Corrib, another gas project but one which has been beset with massive problems, primarily due to years of orchestrated protests of a kind never originally anticipated by operator Shell but which is at last being developed.
Since 2000, only 14 exploration wells have been drilled offshore Ireland. Despite this, four oil, gas and gas condensate discoveries were made – Dooish and Bandon off the west coast, and Old Head and Schull off the south coast. Last year, only one well was drilled (Barryroe in the North Celtic Sea Basin, off Cork) and, in March this year, operator Providence ran a successful flow test.
However, only one well has been drilled in the Atlantic Frontier Rockall Basin since 2005 and no drilling at all took place in the Porcupine Basin during the same period.
Poor seismic data coverage is recognised as the biggest single impediment to exploration in these frontier basins
As reported in Energy on various occasions over the past nearly 10 years, the prime mover in trying to realise Ireland’s offshore hydrocarbon dreams is Providence Resources.
It is thanks to the skilful persistence of the company’s CEO, Tony O’Reilly, that, early next year, ExxonMobil will spud an exploration well on the huge Dunquin gas prospect on the Irish sector of the Atlantic Frontier.
O’Reilly is the force behind the revival of interest in Frontier discoveries made decades ago and which are now being groomed by Providence in a variety of licence partnerships as future appraisal then development candidates.
Prime among these is Spanish Point (Providence 32%), a condensate discovery that lies in the Main Porcupine Basin some 200km off the west coast.
The licence covers blocks 35/8 & 9 in 400m of water. Discovery well 35/8-2 was drilled by a consortium led by Phillips Petroleum (and included Atlantic Resources, the predecessor company to Providence) in 1981.
Post-drill analysis by Phillips suggested that while the discovery could contain resources of up to 1.1trillion cu.ft of gas and 112million barrels of oil, it was deemed uneconomic at the time.
Providence secured the acreage in 2004, commissioned studies that pointed to 1.4TCF of gas and 160million barrels of oil, but with significant upside potential.
As reported by Energy, Providence farmed out 70% of the licence to Chrysaor in 2009; the company has also secured adjacent acreage. An exploration well is indicated as being the next step.
Furthermore, Providence is out in front with newly-licensed acreage, not least on the Atlantic Frontier.
It is only a few weeks since the company published a technical and resource update on the Irish 11th Round prospect known as Drombeg (block 11/9).
Drombeg lies in about 2,500m of water depth and is some 3,000m below the seabed. The prospect is located in the southern Porcupine Basin, about 220km off West Cork and only 60km from Dunquin.
Providence has run a major seismic inversion programme over Drombeg, which is a Lower Cretaceous prospect, together with an assessment of its associated prospective resource potential.
Earlier this year, initial rock physics modelling and seismic inversion work was carried out by Ikon Science over key 2D Drombeg seismic lines which exhibited a marked seismic anomaly.
This initial work modelled the Drombeg anomaly to be consistent with the presence of thick hydrocarbon bearing sandstone intervals. At that time, the company also confirmed that a large Jurassic fault block closure, with a pronounced crestal fluid escape feature, had been also identified beneath the Drombeg Lower Cretaceous prospect.
Results from this new inversion study, together with a volumetric analysis of the Lower Cretaceous interval were presented at the Atlantic Ireland Conference last month.
In essence, the analysis of the primary Drombeg seismic anomaly has indicated a recoverable P50 prospective resource potential of 872million barrels oil equivalent.
Providence and 20% licence partner Sosina, accept that it will be necessary to gather further technical data, including 3D seismic, in order to better assess the ultimate resource potential of the Drombeg prospect. Further similar Lower Cretaceous seismic anomalies have been identified both laterally offset to, as well as vertically stacked with, the Drombeg prospect providing further resource growth potential.
Two separate stratigraphic, but vertically stacked objectives have also been identified in the overlying Lower Cenozoic and underlying Upper Jurassic.
The Lower Cenozoic feature is interpreted to comprise a deep-water basin floor fan covering some 295sq km and which exhibits marked amplitude versus offset (AVO) anomaly.
The deeper Upper Jurassic feature is mapped as a large tilted fault block structure with around 140sq km of closure. A notable fluid escape feature has been interpreted at the crest of the Upper Jurassic tilted fault block and which appears to be acting as a hydrocarbon migration path into both the overlying Drombeg Lower Cretaceous and Lower Cenozoic target intervals.
Providence says this fluid escape feature is significant in that it suggests an oil remigration model at Drombeg which is similar to that which has been proposed for the successful BP-operated Foinaven and Schiehallion fields in the West of Shetland sector.
John O’Sullivan, technical director of Providence, says: “Recent successful discoveries, both in West Africa and South America, have highlighted the enormous potential of the Lower Cretaceous deepwater clastic exploration plays of the Central Atlantic.
“We believe that the results of the Drombeg seismic inversion signal that this significant play may well extend into the North Atlantic Conjugate Margin and, more particularly, into the southern Porcupine Basin.
“The Ikon seismic inversion work, which is consistent with a model supporting the presence of hydrocarbons over a very large area at Drombeg, is hugely encouraging and becomes compelling when considered in tandem with the other associated direct hydrocarbon indicators. Initial feedback from the industry has been very positive with the prospect creating much interest amongst deepwater exploration operators.”
What is brilliant about Providence is that it is willing to talk about its findings . . . far more so that the majors and most of its exploration peer group.