The quake struck at 10:32 p.m. local time (0132 GMT) about 15.6 km (9.7 miles) south-southwest of Coquimbo, the USGS said. The quake was 53 km (33 miles) below the surface, a relatively shallow tremor that shook homes and had some worried about a possible tsunami.
The Pacific Tsunami Warning Center, however, quickly discarded a tsunami threat following the tremor.
A Reuters witness reported minor damage to older buildings and power outages in the nearby coastal city of La Serena, a popular beach town about 400 kilometers (250 miles) north of Santiago.
“It felt very strong...the tourists were very nervous, but nothing serious happened,” Camila Castillo, a receptionist at a hotel in La Serena, told Reuters.
Chilean miner Antofagasta Plc said operations were normal at its Los Pelambres copper mine following the nearby earthquake.
Chile, located on the so-called “Pacific Ring of Fire,” has a long history of deadly quakes, including a 8.8 magnitude quake in 2010 off the south-central coast, which also triggered a tsunami that devastated coastal towns.
But death and destruction are limited by strict construction codes especially designed to withstand earthquakes.