The quake jolted Qinghai province at about 6am local time, the USGS said.

China's official Xinhua News Agency said the Chinese seismological observatory recorded the quake's magnitude at 5.1. The agency did not report any casualties.

The epicenter of the earthquake was 50 kilometres east of Da Qaidam district, in northern Qinghai, and 1,800 kilometres west of Beijing, the USGS said.

The population of the county seat, Da Qaidam town, is about 15,000.

The quake is the second the remote area has seen in three days.

On Monday, a magnitude 6.5 earthquake struck, resulting in a few injuries. -- AP