HOUSTON, Nov. 22 (Xinhua) -- The number of active drilling rigs in the United States fell to 583 this week, down by one from the previous week and by 39 from a year ago, according to the weekly data released Friday by Houston-based oilfield services company Baker Hughes.
These active drilling rigs include 479 oil rigs operating in the U.S. oil fields, up by one from the previous week; 99 gas drilling rigs, down by two from last week; and five miscellaneous rigs, the same as last week.
The rigs include 568 land drilling rigs, two inland water rigs, and 13 offshore drilling rigs.
Of them, 46 are directional drilling rigs, 521 are horizontal drilling rigs and 16 are vertical drilling rigs.
The Permian Basin in western Texas and eastern New Mexico has been the largest source of shale oil production growth in the United States, an engine of supply growth outside the Organization of the Petroleum Exporting Countries in the past years.
