March North Sea daily oil output to fall 7 pct

* March daily output to average 1.902 mln bpd

* Overall volumes up 3 pct at 59.02 mln barrels

* Spring refinery maintenance will limit demand

By Claire Milhench

LONDON, Feb 12 (Reuters) - North Sea daily oil output tracked by Reuters is set to fall by 7 percent in March from February, but traders said this probably would not be enough to balance the market as refiners head into seasonal maintenance.

Output from 12 of the main British and Norwegian crude streams will average 1.902 million barrels per day (bpd) in March, down from a revised 2.046 million bpd in February.

But demand is already falling as refiners in Europe are beginning to enter spring turnarounds. Around 1 million bpd of refining capacity is expected to go offline in March and April, according to Reuters data and industry sources.

This is likely to weigh on North Sea crude differentials and Brent crude oil futures, traders and analysts said.

"Crude seasonality sees slowing refinery runs in the Atlantic (Frankfurt: 98S.F - news) basin, which would limit any further gains for crude until later into the spring months," said Andrey Kryuchenkov, an oil analyst at VTB Capital in London.

March barrels are already being offered at much lower levels to February crude, with Forties offered at dated Brent plus 80 cents on Tuesday, down from the last trade in mid-January at dated Brent plus $1.45.

"I don't think March is going to expire too strongly. There will be a good chunk of European turnarounds in March/April," one trader said.

The month-on-month fall in daily loadings has been accentuated by February being a much shorter month than March. Overall production from the 12 crude streams is actually up 3 percent in March to 59.02 million barrels, from 57.27 million barrels in February.

March's overall volumes were boosted by stronger production from Norway's Asgard, Alvheim and Grane, and Denmark's DUC.

Swedish independent Lundin Petroleum (Other OTC: LNDNF - news) , which has a stake in Alvheim, said in a year-end report that it expected two production wells to come back on stream in February. The wells have been shut-in since January 2013 due to integrity issues.

But the four crude streams that underpin the Brent benchmark - Brent itself, Forties, Oseberg and Ekofisk (BFOE) - will load just 890,000 bpd in March, down from a revised 1.008 million bpd in February.

February's volumes have been boosted by deferrals from January. Brent and Forties gained a cargo apiece, and Ekofisk gained four from January, although a separate February cargo is thought to have been dropped.

THE FORTIES FACTOR

"Seasonal demand will play a bearish factor when it comes to the Brent price but a lower Forties output tends to provide support to oil prices at the same time," said Abhishek Deshpande, an oil analyst at Natixis (Paris: FR0000120685 - news) in London.

"It's a bit too early to say as some of the oil might very well be deferred to March from February, pushing their monthly loading numbers up," he added.

At least six February Forties cargoes have been pushed off their original loading dates already following four unplanned outages at the Buzzard oilfield this year. Buzzard is the biggest single contributor to the Forties stream.

No Forties cargoes have been deferred from February into March as of yet, but market participants are cautious. Nine weeks of maintenance have been scheduled at the field for 2014, according to equity owner Suncor.

Whilst further outages and deferrals will provide short-term support to the market, this is likely to be offset by lower demand from Asia in March. South Korean refiners have been steady buyers of North Sea crude since last September, but no VLCC bookings have yet been sighted for March.

This is because three of the four South Korean refiners will carry out maintenance in the second quarter.

"April could be stronger - there should be some more South Korean interest, but none in March because of the Asian turnarounds," a trader said.