HARRAH, Okla. (AP) â?? The U.S. Geological Survey reports three moderate earthquakes have been recorded in central and northwestern Oklahoma.
The USGS says a magnitude 4.0 temblor was recorded at 10:44 a.m. Tuesday near Harrah, about 25 miles east of Oklahoma City.
No injuries or damage are reported.
Also, quakes of magnitude 3.4 and 3.5 were recorded just seconds apart at 1:25 a.m. about 15 miles northwest of Fairview â?? about 90 miles northwest of Oklahoma City.
The number of magnitude 3.0 or greater earthquakes has skyrocketed in Oklahoma, from a few dozen in 2012 to more than 900 last year.
Scientists have linked the increase to the underground disposal of wastewater from oil-and-gas production. State regulators are asking oil and gas companies in northwest and central Oklahoma to reduce their wastewater disposal wells.