Oil-drilling activity in the U.S. has accelerated to a pace not seen in a generation as energy companies, oilfield contractors and landowners rush to exploit newly profitable sources of crude.

The number of rigs aiming for oil in the U.S. is the highest since at least 1987, according to Baker Hughes. The 818 rigs tallied by the oilfield-service company last week are nearly double last year’s count and about 10 times the number in the late 1990s.

While the drilling surge is unlikely to yield enough crude to alter the global oil-supply picture, analysts predicted that the new activity, centered on so-called unconventional reservoirs, could greatly boost domestic oil production and help offset declining output in Alaska and the Gulf of Mexico.

Read more – Oil-Drilling Boom Under Way