TAKING THE PULSE: Natural-gas woes in North America likely will weigh on oilfield-services companies' third-quarter results, as prices struggle after hitting a 7 1/2-year low in September. International markets, with a bigger oil focus, haven't skidded as far. Though rig counts have edged up amid recent optimism about prices recovering, they are far off last year's peak. Meanwhile, Baker Hughes Inc. (BHI)'s impending $6 billion takeover of BJ Services Co. (BJS) has the potential to help it challenge international giants Halliburton Co. (HAL) and Schlumberger Ltd. (SLB).

COMPANIES TO WATCH:

Halliburton Co. (HAL) - reports Oct. 16

Wall Street Expectations: Analysts polled by Thomson Reuters project earnings of 26 cents a share on revenue of $3.42 billion. A year earlier, Halliburton reported a 2-cent loss on debt-retirement costs and other items while revenue was $4.85 billion.

Key Issues: Halliburton has been winning contracts in Mexico and Brazil, but it remains unclear whether international growth can offset natural gas declines in the U.S. The company, more exposed to North America than its rivals, has expected major customers to continue seeking discounts.

Weatherford International Ltd. (WFT) - reports Oct. 19

Wall Street Expectations: Analysts are looking for earnings of 13 cents on revenue of $2.16 billion, down from 53 cents and $2.54 billion, respectively.

Key Issues: The company continues to seek growth in Mexico and gained a foothold in Russia with its $490 million acquisition of the oilfield unit of BP PLC's (BP) Russian joint venture. Weatherford, like Schlumberger, gets only about 30% of its revenue from North America.

Nabors Industries Ltd. (NBR) - reports Oct. 20

Wall Street Expectations: The company is projected to post a profit of 17 cents on revenue of $821 million, sharply lower than the prior year's 73 cents and $1.41 billion.

Key Issues: North America's largest land-drilling contractor needed to rely on its international business, as well as smaller Alaskan and U.S. offshore businesses, in the latest quarter. While lower-48 land drilling appeared to have stabilized, the company projected in July that the segment's third-quarter profit could fall another 50%.

Schlumberger Ltd. (SLB) - reports Oct. 23

Wall Street Expectations: Analysts forecast a profit of 63 cents on revenue of $5.5 billion. A year earlier, the company reported earnings of $1.25 a share and revenue of $7.26 billion.

Key Issues: While North American operations may have seen their worst declines already, in July Schlumberger executives predicted things wouldn't get much better this year. Chief Executive Andrew Gould said at the time that oil prices would need to remain about $70 a barrel toward year's end to sustain any revival in global exploration and development.

Baker Hughes Inc. (BHI) - reports Nov. 4

Wall Street Expectations: The company is seen posting a profit of 36 cents a share on revenue of $2.27 billion, down from $1.39 and $3 billion, respectively.

Key Issues: Baker Hughes will have an expanded repertoire of services after its anticipated acquisition of BJ Services, whose main business is pressure pumping, or sending chemicals down oil and gas wells to improve production. (The deal is expected to close by the end of the year.) Weakness in North America is likely to continue to hurt results, while international markets have been better.

(The Thomson Reuters estimate and year-earlier earnings may not be comparable due to one-time items and other adjustments.)

-By Tess Stynes, Dow Jones Newswires; 212-416-2481; tess.stynes@dowjones.com