UPDATE 1-CNOOC Q3 rev down 23 pct, says projects on track

* Q3 revenue down 23 pct, output up 18 pct

* Says major development projects are on track

* Shares end down 4.5 pct before results, up 8.4 pct in Q3

(Writes through with details, background)

By Sui-Lee Wee

HONG KONG, Oct 29 (Reuters) - China's top offshore oil and gas producer CNOOC Ltd produced 18.4 percent more oil and gas in the third quarter but concerns linger over its future production levels due to its lack of acquisitions since 2006.

CNOOC (0883.HK)(CEO.N) along with its global peers such as Exxon Mobil (XOM.N) and Royal Dutch Shell Plc (RDSa.L) have also been hit by a steep drop in oil prices from their 2008 peak and analysts say the outlook for oil and gas producers remains grim, with crude prices likely to stay weak this year.

CNOOC said higher contributions from new fields offset a disruption at an offshore gas field caused by a typhoon in September.

But its total revenue fell 23.1 percent to 23.8 billion yuan due to the sharp fall in crude prices. This compares with a forecast by Sanford C. Bernstein of 21.6 billion yuan, one of the few analysts to estimate quarterly revenues for CNOOC.

CNOOC's lack of acquisitions since 2006 has sparked concerns over its production growth, putting more pressure on it to secure more outbound deals such as the highly contested Jubilee oil field in Ghana.

"The company's major development projects progressed on track," CNOOC said in a statement on Thursday.

On Sept. 14, CNOOC was forced to shut down its offshore gas field Huizhou 21-1 for three weeks, after a typhoon caused damage. The field has since resumed normal production. [ID:nPEK142434].

STEEP FALL IN CRUDE

CNOOC's overall oil and gas output rose to 647,382 barrels of oil equivalent in the July to September period.

While benchmark U.S. crude oil futures CLc1 bounced to $68 a barrel in the third quarter, up from nearly $60 in the second quarter, they are still down from $118 a year ago.

The company's average oil selling price was 36.6 percent lower at $67.83 per barrel in the quarter.

Shares in CNOOC fell 4.5 percent on Thursday ahead of the results, compared to a 2.3 percent fall on the benchmark index .HSI. CNOOC rose 8.4 percent in the third quarter, versus PetroChina (0857.HK) (601857.SS), which rose 1.9 percent and the Hang Seng Index, which gained 14 percent.

(Editing by Valerie Lee)