UPDATE 2-Portugal's Galp Q1 adjusted net down 8.4 percent

(Adds revenue figures, CEO statement, details)

LISBON, May 20 (Reuters) - Portuguese oil company Galp Energia SGPS SA (GALP.LS: Quote, Profile, Research, Stock Buzz) posted an 8.4 percent decline in quarterly adjusted net profit on Tuesday, hit by lower refining margins due to the weak dollar, but the results were slightly higher than expected.

First-quarter net profit reached 109 million euros excluding non-recurring items and stock effects, down from 119 million euros a year earlier.

Galp said in a statement that while refining and distribution was weak, its gas and power, exploration and production unit had strong operating results.

"The combination of weaker refining margins and a weaker dollar hurt the results," Chief Executive Manuel Ferreira de Oliveira told reporters.

Earnings before interest, taxes, depreciation and amortisation (EBITDA) rose 3.3 percent to 234 million euros. Refining margins fell 46.9 percent.

Analysts polled by Reuters had forecast adjusted net profit of 104 million euros and EBITDA of 218 million euros.

Revenue rose 27 percent to 3.493 billion euros, while sales at the refining and distribution unit rose 25.7 percent to 3.056 billion euros.

Galp, which has upstream business in Angola and participates in an exploration consortium in Brazil, said sales by its exploration and production unit rose 55 percent to 65 million euros.

Galp's shares have been driven in recent months by the prospect of starting to drill, together with partner Petrobras (PETR4.SA: Quote, Profile, Research, Stock Buzz), the huge reserves that have been found in Brazil's Santos Basin, including the so-called BM-S-8 block.

"The consortium met yesterday to deliberate about the communication that will be made to the market," Ferreira de Oliveira said, when asked about the block.

Analysts have estimated that the BM-S-8 block has 2.5 billion barrels of reserves. Results of testing at the block are expected to be ready before the end of the second quarter. (Reporting by Ruben Bicho and Axel Bugge; Editing by David Holmes)