The Barryroe oil and gas field was held under Licence 1/11 incorporating part blocks 48/22,48/23, 48/24,48/27,48/28,48/29 and 48/30; covering an area of 614 sq. km. and lying along the axis of the North Celtic Sea Basin.
Celtic Sea Location Map
The Barryroe Licence was held by Lansdowne Celtic Sea Limited (20%), a 100% subsidiary of Lansdowne Oil & Gas plc, and EXOLA DAC (80%), a 100% subsidiary of Providence Resources P.l.c.
A revised application for a Lease Undertaking was submitted in April 2021 to the Department of the Environment, Climate and Communications (DECC).
On 19 May 2023 a letter was received from DECC advising that Eamon Ryan, the Minister, would not grant the Lease Undertaking.
On 28 June 2023 the Company announced that its legal advisors had submitted a letter giving notice under the Energy Charter Treaty (“ECT”) seeking compensation.
Part of the Barryroe acreage lies beneath the Seven Heads Gas Field, with the boundary between the two concessions lying at 4,000ft (approximately 1,250m) sub-sea.
The reservoir sands in the Barryroe Field lie in the Lower Cretaceous Wealden sequence.
The original discovery well on Barryroe, 48/24-1, was drilled by Esso in 1973 and tested oil at an aggregate rate of c. 1,300 barrels per day from sandstones in the Middle Wealden.
An appraisal well, 48/28-1, was drilled by Esso in 1974 and again tested oil from a Middle Wealden sandstone at a rate of 1,527 barrels per day.
A third well, 48/24-3, was drilled by Marathon in 1990 and this tested oil from the Basal Wealden sandstone at an aggregate rate of 1,619 barrels per day.
Lansdowne participated in the successful appraisal well, 48/24 – 10z, which was drilled in late 2011/early 2012.
48/24-10z Petrophysical log.
This well found a Basal Wealden sandstone sequence, around 100 ft thick. A shallower gas-bearing sandstone (C Sandstone) is separated from a deeper oil-bearing sandstone (A Sand), by an intervening siltstone sequence.
The A Sandstone was tested and flowed at a rate of 3,514 barrels of oil per day and 2.93 million standard cubic feet per day of gas (combined giving a total rate of c. 4,000 barrels of oil equivalent per day). The oil is light, 43 degrees API, with a wax content of 17%.
Following the successful testing of the A Sandstone, the C Sandstone was also perforated, and a combined test was run over both zones.
This second test flowed at a restricted rate of 7 million standard cubic feet per day of gas, and 1,350 barrels of oil per day (2,516 barrels of oil equivalent per day).
The C Sandstone proved to be highly productive and modelling of the pressure data indicated that a co-mingled flow rate of 17 million standard cubic feet per day and 3,350 barrels of oil per day (6,183 barrels of oil equivalent per day), should be achievable from the 10z well at a flowing well head pressure of 500 pounds per sq. inch.
Barryroe Schematic Cross-Section
Following acquisition and interpretation of the 2011 3D seismic data, together with the subsequent drilling and testing of the 48/24-10z Barryroe appraisal well in 2012, Providence retained the services of Netherland Sewell & Associates Inc. (NSAI) to carry out a third party contingent resource audit (CPR) of the in-place hydrocarbon and recoverable resources for the Basal Wealden oil reservoir. NSAI reported that the Basal Wealden oil reservoir has 2C in-place gross on-block volume of 761 MMBO with recoverable resources of 266 MMBO and 187 BCF of associated gas, based on a 35% oil recovery factor. A third party (CPR) audit of the overlying Middle Wealden, which was carried out by RPS Energy (RPS) in 2011, reported a 2C in-place gross on-block volume of 287 MMBO with technically recoverable resources of 45 MMBO and 21 BCF of associated gas, based on a 16% oil recovery factor.
The total combined audited gross on block 2C recoverable resources at Barryroe therefore amount to 346 MMBOE, comprising 311 MMBO and 207 BCF. The following table summarises the range of total gross audited on-block Barryroe oil resources:
1C 2C 3C
(MMBO) (MMBO) (MMBO)
Basal Wealden STOIIP (NSAI) 338 761 1,135
Basal Wealden Recoverable (NSAI) 85 266 511
Middle Wealden STOIIP (RPS) 31 287 706
Middle Wealden Recoverable (RPS) 4 45 113
TOTAL STOIIP 369 1,048 1,841
TOTAL RECOVERABLE OIL RESOURCES 89 311 624
Note: The table above excludes recoverable solution gas (i.e. 207 BCF or 34.5 MMBOE in the 2C case)
Further incremental resource potential has been identified in logged hydrocarbon bearing intervals within stacked Lower Wealden and Purbeckian sandstones which Providence has previously estimated contains total associated P90, P50 & P10 in place oil resources of 456 MMBO, 778 MMBO & 1,165 MMBO respectively. As there is currently limited reservoir and well test data available over these two intervals, future well data over these specific zones would be required in order to firm up their associated final recoverable resource estimates.