The number of active drilling rigs in the United States rose to 641 this week, up by nine from the previous week but down by 122 from this time last year, according to the weekly data released by Houston-based oilfield services company Baker Hughes on Friday.
These active drilling rigs included 515 oil rigs operating in U.S. oil fields, up by two from the previous week; 121 gas drilling rigs, up by eight; and five miscellaneous rigs, down by one.
The rigs included 619 land drilling rigs, three inland water drilling rigs, and 19 offshore drilling rigs.
Of them, 57 were directional drilling rigs, 567 were horizontal drilling rigs and 17 were vertical drilling rigs.