HOUSTON, Aug. 26 (Xinhua) -- The number of active drilling rigs in the United States rose to 765 this week, up by three from the previous week and 257 from last year, according to the weekly data released Friday by Houston-based oilfield services company Baker Hughes.
These active drilling rigs included 605 oil rigs operating in the U.S. oil fields, up by four from the previous week; 158 gas drilling rigs, down by one from last week; and two miscellaneous rigs, the same as last week.
The rigs included 744 land drilling rigs, three inland water rigs, and 18 offshore drilling rigs.
Of them, 40 are directional drilling rigs, 694 are horizontal drilling rigs and 31 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.
