Predictions for a single gas well in East Yorkshire suggest initial production could exceed many entire fields in the North Sea.
The modelling, published by Union Jack Oil plc today, is based on data from a well test at the West Newton-A site.
In a statement, the modelling predicted a single well accessing the gas section of the Kirkham Abbey formation would initially produce an average of 35.6 million standard cubic feet of gas per day (mmscfd).
A single well in the oil section of the formation would initially produce 1,000 barrels of oil per day (bopd), the modelling said.
The modelling, by RPS Group, was based on flow rate analysis from an extended well test (EWT) last year on the West Newton-A2 vertical well. The results assume a horizontal well and acid stimulation. They do not take into account any natural fracturing in the Kirkham Abbey formation, which could increase flow rates.
If accurate, the modelling would put gas production from a single well at West Newton-A in the top six of all UK gas fields, both on and offshore.
It would exceed average daily gas production from each of the Barque, South Sean, Chiswick and West Sole fields in the North Sea and the Calder field in the Irish Sea. This is based on 2021 data, when all these fields were in the top 10.
Only five offshore gas fields (Cygnus, Sillimanite, Leman, South Morecambe and Breagh) would exceed the West Newton-A modelled well, based on 2021 figures.
Compared with UK onshore wells, the predicted gas production would be 35 times higher than the largest producer, again based on 2021 data.
There is currently no gas pipeline connection at West Newton-A and formal plans for the site do not include one. Instead, during production, gas is expected to power generators on the site.
During well testing, gas would burned in a flare. There is a flaring budget of 330 mmscf of gas for the life of West Newton-A. If the predicted gas volumes were confirmed and all the gas was flared, this budget would be used up in under 10 days.
If the modelled extraction rate was confirmed, it would be more than double that from the UK’s second largest onshore producing field, at Welton in Lincolnshire.
It would also exceed the level of 884 bopd reported in September 2021 from well tests at Wressle, North Lincolnshire.
The modelled well would be behind only Wytch Farm, in Dorset, in the top UK onshore fields. Production at Wytch Farm in September 2021, the latest figure available, was 12,181 bopd.
If the predicted oil production were confirmed, a single well at West Newton would exceed the site’s proposed storage capacity of 3,600 barrels in fewer than four days.
The operator of the West Newton-A site, Rathlin Energy, is currently seeking planning permission for 20 years of hydrocarbon production and four more vertical wells, in addition to the existing two.
The application sets a maximum of 10 tankers a day to remove oil during the production phase. The larger UK tankers carry about 220 barrels of oil. So, if confirmed, the single modelled well’s oil production would require nearly half the available tankers visiting the site every day.
Wells and stimulation
Rathlin Energy has said it might drill sidetrack or lateral wells from the current two and future four boreholes at West Newton-A.
The RPS modelling concluded that the Kirkham Abbey formation could deliver substantially higher production rates from horizontal wells, rather than vertical wells.
Union Jack, an investor at West Newton-A, said:
“The [RPS] report also concluded that … most of the acid stimulation carried out during the EWT only interacted with a small section of the perforated intervals due to the permeability contrast across the Kirkham Abbey formation in both wells.
“This suggests that potential flow rates from wells in the Kirkham Abbey reservoir would benefit from a conventional optimised acid stimulation programme that includes active diversion techniques.”
David Bramhill, executive chairman of Union Jack, said:
“This initial analysis confirms the significance of the in-place resource and crucially, has de-risked the project by indicating the potential recovery of what we can now confirm to be high quality light oil, in addition to good quality gas.
“The mass of data obtained from the operation has allowed the modelling of potential flow rates, independently assessed for the first time.”
- This is not the first time onshore hydrocarbon companies have suggested wells could equal or exceed North Sea production. In 2016, the Horse Hill-1 well in Surrey was said to show “North Sea-like oil flows”. Since production began at Horse Hill in March 2020, it has extracted an average of 113 bopd.