DUBAI, Sept 7 (Reuters) - Stock markets in the Gulf were mixed in quiet early trade on Wednesday as some investors stayed away from the bourses ahead of market closures next week for Eid al-Adha holidays.

Riyadh's main index was down 0.2 percent in the first hour. Emaar the Economic City rose 2.9 percent after it said on Wednesday that an affiliate had obtained a 2.7 billion riyal ($720 million) Islamic loan from banks to finance the second phase of building King Abdullah Port.

Amana Cooperative Insurance jumped 3.5 percent after the board recommended a 56.3 percent share capital reduction through a reverse stock split of 1.125 shares for every two shares held.

But petrochemical shares were weak with giant Saudi Basic Industries falling 0.3 percent. Producers' margins are being squeezed by unfavourable oil-derivative product spreads after Brent crude, which hit a one-week high of $49.40 per barrel on Monday after Russia and Saudi Arabia agreed to cooperate on stabilising the oil market, fell back to $47.60.

Qatar's index dropped 0.9 percent as half of traded shares retreated. Islamic lender Masraf Al Rayan declined 1.4 percent.

Dubai's index slipped 0.2 percent with most trade concentrated in small caps. Drake & Scull dropped 0.9 percent.

But Gulf Navigation added 1.7 percent after the company said it had signed a new settlement agreement in its long debt dispute with Nordic American Tankers and that its debt to Nordic American had now been settled fully. It gave no details.

Abu Dhabi's index was flat in quiet trade. Dana Gas pulled back 1.7 percent but First Gulf Bank was up 0.4 percent.

(Reporting by Celine Aswad; Editing by Andrew Torchia) ((celine.aswad@thomsonreuters.com; +971 4 4536886; Reuters Messaging: celine.aswad.thomsonreuters.com@reuters.net))