Halliburton, the largest hydraulic fracturing operator in Weld County, reported Wednesday a third-quarter profit of $602 million, down from $683 million a year earlier.

Halliburton, which employs more than 500 people in Brighton, reported revenue of $7.1 billion vs. $6.5 billion the previous third quarter. The company posted $7.2 billion in revenue during the second quarter.

Revenue in North America dipped 5 percent mainly because of pricing pressure in fracking; the increased cost of guar, a substance used in fracking; and disruptions from Hurricane Isaac, CEO Dave Lesar said in an earnings statement.

"We are also seeing activity reductions by some of our customers as they continue to moderate activity to operate within their stated 2012 budgets," he said.

He noted an 18 percent drop in the number of natural-gas rigs operating in the United States. The total number of rigs operating nationwide has declined 2 percent relative to the third quarter of last year.