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UPDATE 2-Halliburton revenue drops more than expected as shale demand slows

By Shariq Khan and Liz Hampton

(Adds details about segments, shares)

By Shariq Khan and Liz Hampton

Oct 21 (Reuters) - Halliburton Co reported a bigger-than-expected 10% drop in quarterly revenue on Monday, as the oilfield services provider battled lower demand from shale oil producers in North America, its biggest market.

Revenue from North America, which accounts for more than half of the company's total, fell 21% in the third quarter, primarily due to lower pressure pumping activity and pricing.

Halliburton, the largest provider of hydraulic fracking fleets, said completion and production revenue fell 16% in the three months ended Sept. 30.

Larger rival Schlumberger said on Friday it had recorded a $1.58 billion goodwill impairment charge related to its pressure pumping business in North America.

"These results from Halliburton bring into crystal-clear focus the speed with which North America (NAM) land well construction and completion activity eroded during course of Q3," Tudor, Pickering, Holt & Co analysts wrote in a note.

Oilfield service providers are struggling with reduced spending by oil and gas producers as investors push for higher buybacks and dividends rather than growth in a weak oil price environment.

Halliburton was forced to cut 650 jobs across Colorado, Wyoming, New Mexico and North Dakota amid the slowing oil and gas activity, while smaller rival ProPetro Holding Corp cut about 150 workers, sources told Reuters.

Net profit attributable to Halliburton fell to $295 million, or 34 cents per share, in the third quarter ended Sept. 30, from $435 million, or 50 cents per share, a year earlier.

Analysts had on average estimated 34 cents per share, according to Refinitiv IBES data.

Revenue fell to $5.55 billion, below analysts' average estimate of $5.81 billion.

Shares of the company were unchanged in premarket trading, having fallen about 31% so far this year through Friday's close. The S&P 500 Energy sector index has fallen just 0.8% during the same time. (Reporting by Shariq Khan and Taru Jain in Bengaluru; Editing by Sriraj Kalluvila)