Done Before … for Many Years
Exploration, appraisal and production of natural gas in the Irish Sea has followed a very conventional route that has been developed in the UK since the early 1980s.
That route begins with an analysis and understanding of the regional geology and estimation as to the most likely or “prospective” locations for finding gas. Seismic data is acquired to refine the prospective locations and plan an exploration well. The exploration well is drilled through the full geological section of rock in order to acquire a full suite of data of the gas prospective layers and to provide as much regional and academic data for industry and the British Geological Survey. Possible gas resource volumes are estimated at this point.
Additional appraisal seismic data may be acquired specifically to further delineate a gas discovery and to plan the location of appraisal wells. The appraisal drilling provides extensive data to understand how to develop the gas (number of wells, location of wells) and a refined estimation of gas resource volumes. A field development plan (FDP) is written and submitted to government for review, changes and consent. The FDP document contains details on all aspects of the gas development; geology, wells, infrastructure, gas production profiles and royalty revenues to Government.
To understand the methods likely to be required in the Crogga Field, it is important to understand what we know of the local geology.
Gas production from The Irish Sea:
Since 1985 South Morecambe has produced 5,000Bcf of gas and since 1994 North Morecambe has produced 1,000Bcf of gas. This gas is piped to the Rampside Gas Terminal in Barrow-in-Furness on the site of the now decommissioned and demolished Roosecote coal-fired power station.
In total, from the Irish Sea, North and South Morecambe, along with other adjacent natural gas fields, have produced 8,000Bcf since 1985.
Currently the main gas fields in the Irish Sea are owned by UK company Spirit Energy (weblink) (previously Centrica, previously British Gas) and UK company Chrysaor (weblink) (previously ConocoPhillips, previously Burlington Resources) both with their operational bases in Aberdeen. The Rampside Gas terminal is operated by Spirit Energy.