The earthquake occurred at 1:30 a.m. local time, according to the USGS, and its depth was about 50 miles deep.
Its epicenter was in a remote area some 200 miles (320 kilometers) southwest of the Baluchistan capital of Quetta, said chief Pakistani meteorologist Arif Mahmood, not far from the Afghan border.
The closest town to the epicenter was Dalbandin, with a population around 15,000 people, and is so remote that the nearby Chagai hills were the site of Pakistan's 1998 nuclear tests.
No injuries were initially reported.
Damage reports included collapsed mud houses.
The quake was felt as far away as India and the United Arab Emirates.
The Associated Press contributed to this report.