HOUSTON, Dec. 6 (Xinhua) -- The number of active drilling rigs in the United States rose to 589 this week, up by seven from the previous week but down by 37 from a year ago, according to the weekly data released Friday by Houston-based oilfield services company Baker Hughes.
These active drilling rigs include 482 oil rigs operating in U.S. oil fields, up by five from the previous week; 102 gas drilling rigs, up by two from last week; and five miscellaneous rigs, the same as last week.
The rigs include 572 land drilling rigs, two inland water rigs, and 15 offshore drilling rigs.
Of them, 49 are directional drilling rigs, 526 are horizontal drilling rigs and 14 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, and an engine of supply growth outside the Organization of the Petroleum Exporting Countries in the past years. ■