The end of an era in N. Sea oil exploration and discovery was marked today (2 May 2017) with the ‘topsides’ of the Shell’s Brent Delta platform – which has now been severed from its ‘sea-legs’ – due to arrive for onshore break-up at Hartlepool.
So sweet and pure was its oil, that ‘Brent crude’ became an industry byword for high-quality N. Sea oil from Scotland – the platform and field lies 115 miles north-east of Shetland – and was the benchmark price-maker on world markets.
The 24,000 tonne Brent Delta platform topsides sat atop a three-legged gravity-based concrete structure in 140 metres of water. Unusually for a platform, the legs of Brent Delta are made of concrete which makes it much more difficult to decommission than those made of steel.
Allseas, the company which operates the decommissioning vessel Pioneering Spirit, claimed that it has set a world lifting record with the removal of the platform – one of four which is due to be removed from the Brent field in the coming years.
The iconic Brent field first started pumping oil from the N. Sea in 1976. At its peak in 1982, the four platforms in the field produced more than half a million barrels of oil a day.
Shell is seeking regulatory approval to leave the concrete legs for the Brent Delta platform in-situ in the North Sea – and decommissioning policy which provoked international environmental outrage in 1994-5 when it first tried to do likewise with the Brent Spar waste oil storage tanks. The Brent Spar was later towed to Norway for breaking-up.