* Petchems, banks strong in Saudi
* Qatar weakens to 18-month closing low
* Dubai's DSI up after chairman resigns
* Dana Gas rises again in active trade
* Egypt's Qalaa Holding at 16-month peak
DUBAI, Sept 10 (Reuters) - Stock markets in the Middle East were mixed in narrow ranges on Sunday, with banks and petrochemicals supporting Saudi Arabia while Qatar edged down to a fresh 18-month closing low.
The Saudi index rose 0.2 percent. All but two of the 14 listed petrochemical shares advanced after a pick-up in oil prices at the end of last week, with small polymer maker Nama Chemicals surging 9.5 percent in unusually heavy trade.
Two-thirds of the 12 listed banks rose with Banque Saudi Fransi, the best performer, climbing 3.8 percent.
Qatar's index edged down 0.1 percent to 8,667 points, its fifth straight session of decline; foreign funds were net sellers, bourse data showed. Doha Bank slipped 0.6 percent.
Dubai's index edged up 0.1 percent, as builder Drake & Scull rose 1.1 percent in active trade after news that the company's chairman, Majid al Ghurair, had resigned for "personal reasons."
DSI will elect a new chairman at board of directors meeting on Tuesday, and investors may hope the change could help the company rebound from losses caused by a slump in the regional construction industry.
In Abu Dhabi, Dana Gas added 1.2 percent and was again Abu Dhabi's most heavily traded stock, accounting for almost two-thirds of trading volume.
Last week it surged 28 percent in response to the company's deal to receive hundreds of millions of dollars in payments from the government of Iraqi Kurdistan. The deal clears the way for Dana to resume expanding gas production in the area over the long term.
Abu Dhabi National Energy climbed 6.4 percent but most other shares fell, dragging the main Abu Dhabi index down 0.2 percent.
In Egypt, the index rose 0.2 percent with investment firm Qalaa Holdings jumping 7.5 percent to a 16-month high. Shares in the company have been strong since last week when one of its mining subsidiaries sold its stake in an Ethiopian company.
* The index rose 0.2 percent to 7,378 points.
* The index edged up 0.1 percent to 3,648 points.
* The index dipped 0.2 percent to 4,446 points.
* The index lost 0.1 percent to 8,667 points.
* The index added 0.2 percent to 13,456 points.
* The index increased 0.4 percent to 6,926 points.
* The index rose 0.1 percent to 1,317 points.
* The index edged up 0.2 percent to 5,057 points. (Editing by Andrew Torchia)