Oilfield services leader Schlumberger Ltd reported lower quarterly earnings on Friday, hurt by weaker energy prices and slowing exploration spending.

Third-quarter net profit sank to $789 million, or 65 cents per share, from $1.54 billion, or $1.25 a share, a year earlier. The results beat the analysts' average estimate by 2 cents per share, according to Thomson Reuters I/B/E/S.

Revenue slumped by about a quarter to 5.4 billion. Oilfield services revenue sank 22 percent to $4.95 billion.

Our outlook for the remainder of 2009 assumes a continued modest recovery in North American gas drilling but no significant improvement in service pricing, Chief Executive Officer Andrew Gould said in a statement.

(Reporting by Christopher Kaufman in New York and Braden Reddall in San Francisco; Editing by Lisa Von Ahn)