An earthquake with a magnitude of 4.5 hit near the north-central Oklahoma city of Cushing on Saturday afternoon, the U.S. Geological Survey said.
The quake was shallow, at a depth of about 1 km (0.6 miles), with its epicenter at 5 km (3 miles) from Cushing, it said. There were no immediate reports of injuries or damage.
It was the second significant quake to hit the state in a day, the USGS said, adding a quake with a 4.4 magnitude hit near Medford, about 1 130 km (80 miles) northwest of Cushing, on Saturday morning.
Cushing is the storage hub for U.S. crude oil, at the nexus of web of pipelines. Bob Noltensmeyer, director of emergency management for the city, said he has not heard of any damage to oil storage facilities due to the earthquake.
Oklahoma and several other central U.S. states have experienced a major increase in earthquakes since 2009. Scientists attribute this to increased underground injection since then of briny wastewater, a byproduct of booming oil and gas production.