UPDATE 1-Maintenance to halve North Sea Forties oil in August

* Forties to load 16 cargoes of 600,000 barrels in August

* Programme cut from 34 cargoes in July

* Cut reflects maintenance, especially to Buzzard oilfield

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By Christopher Johnson

LONDON, July 9 (Reuters) - Oilfield maintenance will more than halve crude oil production from the North Sea Forties stream next month, trade sources said on Thursday, in a move they said could support physical oil prices.

Just 16 cargoes of 600,000 barrels of Forties will load in August, the loading programme shows, with an average of about 310,000 barrels per day (bpd), down from 658,000 bpd in July and 680,000 bpd in June.

Forties is the biggest single component of what is known in international oil markets as Brent Blend, which is in fact a mixture of North Sea Brent, Forties, Norwegian Oseberg and Ekofisk crudes, or "BFOE".

Brent Blend is used as the basis for Brent futures LCOc1 one of the world's two big oil contracts and is used as the basis for pricing numerous grades of crude oil in Europe, the Middle East and Africa.

Oil traders said the big reduction in supply in August reflected a programme of maintenance work on several small fields that feed into the Forties stream, including the Buzzard oilfield, managed by Canadian oil company Nexen (NXY.TO).

Maintenance often affects North Sea oil output in the summer months although the work programme in August appears to be one of the largest seen for some time, traders said.

Buzzard is Britain's largest field, according to output data compiled by industry newsletter Aberdeen Petroleum Report. [NSEA/W]

BUZZARD

The Buzzard oilfield, which yields light but relatively high sulphur crude oil, is scheduled to have four weeks of maintenance in the third quarter and traders said the work will start in the middle of August.

Oil companies loading Forties say they have been told that the sulphur content of the crude is due to fall to just 0.3 percent in the middle of August, from the more usual 0.9 percent, as Buzzard goes down.