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Situated in the East Shetland basin , the Brent is the archetype for many of the fields in the area, consisting of a tilted fault block exposing the eponymous Brent formation next to bounding faults which allowed migration from deeper adjacent "kitchen" areas where the Kimmeridge Clay Formation becomes fully mature and releases hydrocarbons. Unusually on a world-wide scale (but common in this basin), the seal or cap rock for the reservoir (which stops the hydrocarbons from migrating further towards the surface) is also the Kimmeridge Clay. To explain how really requires a diagram. The Brent field is exploited by 5 platforms in an irregular SSW- NNE line. The first in place was the steel-jacket Brent-A (2004, in progress to decomissioning), then three concrete legged platforms (Brent B, C, D) were emplaced to the NNE. A fifth installation, the floating Brent E served as a storage and tanker loading buoy and was installed early in the field's construction. The "spar" design of this installation lead to the name by which it became the best known of the Brent installations (outside the oil industry) - as the infamous "Brent Spar".

Brent Spar

In the late 1990s the Shell/ Esso 'Expro' consortium which operates the Brent field completed installation of a series of oil and gas pipelines for exporting hydrocarbons directly to terminals onshore. This rendered the tanker-loading functions of the Brent Spar irrelevant, and so 'Expro' decided to dispose of it.

There is considerable controversy over how the options for disposal were assessed. Without going into contentious detail, there are allegations that Expro decided to try to dump it in deep water because they wished to establish a precedent for disposing of other platforms in this way. The costs of other options that were proposed at the time are, to say the least, hotly disputed.

Regardless of the politics of this decision, the management of Expro made the decision to go for the deep-water dumping option. In 1995 they attempted to put this plan into operation in the teeth of vocal opposition from various lobby groups (personified by, but by no means restricted to, Greenpeace). Although Greenpeace mounted a high-publicity campaign including repeated occupations of the installation, within the industry there was little doubt that if Expro had decided to stick to it's plans, they would have suceeded in sinking the Spar as planned. However, the loss of hundreds of millions of dollars of sales in fuel sales across Europe due to local campaigns co-ordinated alongside the high-publicity occupations seemed to concentrate the attentions of the money people and Expro backed down from the confrontation.

The Brent Spar was eventually towed into a Norwegian fjord and dismantled to be used as caissons for setting foundations for a new pier. It is debatable whether or not this was actually more or less damaging to the environment than the original deep disposal plan, though on the grounds of "displaying corporate responsibility", it seems to have had the desired public relations effect.