The earthquake's epicenter, at a depth of 7.45 miles, was about 166 miles east-southeast of Hotan, China, and 559 miles east-northeast of Islamabad, Pakistan, the USGS said.
Readings by the China Earthquake Networks Center indicated the earthquake had a 7.3 magnitude, China's state-run Xinhua News Agency reported.
There were no immediate report of casualties or property damage, Xinhua said. Mostly Uyghurs live in the sparsely populated area.
The center reported several aftershocks, including one with a magnitude of 5.7.