AlHijjah 28, 1436, October 12, 2015, SPA -- A series of small earthquakes have been recorded across northern Oklahoma following two moderate earthquakes in the area on Saturday, according to AP. The U.S. Geological Survey reported that nine quakes ranging in magnitude from 2.5 to 3.7 were recorded between 5:07 p.m. Saturday and 5:27 a.m. Sunday. No injuries or damage were reported. Geologists say damage is not likely in quakes below magnitude 4.0. The latest seismic activity comes after a 4.5 magnitude temblor Saturday afternoon near Cushing and a 4.4 magnitude quake Saturday morning southwest of Medford. Cushing is where the world's most important crude oil storage hub is located and it is used to settle futures contracts traded on the New York Mercantile Exchange. Cushing Emergency Management Director Bob Noltensmeyer said Sunday that no significant damage was found, only "shattered nerves." "It's kind of frustrating and irritating," Noltensmeyer said, "because you never know when they're going to happen." The Oklahoma Geological Survey has said it is likely that many recent earthquakes in the state have been triggered by the injection of wastewater from oil and natural gas drilling operations.