The number of active drilling rigs in the United States dropped to 631 this week, down by one from the previous week and by 129 from a year ago, according to the weekly data released by Houston-based oilfield services company Baker Hughes on Friday.
These active drilling rigs included 512 oil rigs operating in U.S. oil fields, unchanged from the previous week; 114 gas rigs, down by one from last week; and five miscellaneous rigs, unchanged from last week.
The rigs included 611 land drilling rigs, three inland water drilling rigs, and 17 offshore drilling rigs.
Of them, 51 were directional drilling rigs, 566 were horizontal drilling rigs and 14 were vertical drilling rigs.
So far, the Permian Basin in western Texas and eastern New Mexico has been the largest source of shale oil production growth in the United States, having become an engine of supply growth outside the Organization of the Petroleum Exporting Countries in the past years.
