SCOTTISH granite has been blamed for the closure of a major North Sea pipeline which experts said would have wide-reaching implications for the oil and gas industry.

The 234-mile long Forties pipeline had to close for three weeks in December after inspections by Ineos discovered a hairline crack.

More than 80 oil and gas platforms and facilities which are connected to the mainland by UK's largest pipeline had to suspend production.

One oil and gas company, Houston-based Apache, said it had to shut down production for a full 13 days and estimated that production would only be operating at a quarter of capacity for a further 10 days.

HeraldScotland:

Ineos, the owner of the Grangemouth oil refinery in Scotland, explained its contractors found the crack where the pipeline system runs over land near Netherley, south of Aberdeen.

“The precise point of the transverse weld of the pipeline was resting on a sharp ridge of granite rock and over time vibration of the pipeline led to the hairline crack,” said Ineos director Tom Crotty.

“It was a failure that BP hadn’t seen before and we don’t expect to see again,” he said.

The shutdown was seen as a serious blow for Ineos, which completed its £200m purchase of the pipeline system from BP two months prior to the discovery of the crack.

The Health and Safety Executive is carrying out an investigation intot he circumstances surrounding the incident.

HeraldScotland:

Mr Crotty in describing the condition of the pipeline post-purchase said: “It was more of a Ford Mondeo than a Mercedes but that is a reflection of the age of the system. We knew that a robust maintenance programme would be essential.”

“We will probably spend more on maintenance than the previous owners, reflecting the fact that this is an older asset.”

The company had said that it was now the only UK company with refinery and petrochemical assets that were integrated in the North Sea, and would serve as a platform for more investments in the region.