The tremor is the latest in a a series of 34 in the region in the last day, the USGS has said. It struck at a depth of 6.2 miles.
Seismic activity is commonplace in the region, located within the so-called Ring of Fire which stretches around the Pacific Basin.
On Monday, the American Geophysical Union tweeted: “An M8.1 #earthquake off the coast of #NewZealand triggered an estimated 300 #landslides on #RaoulIsland, the largest of the #Kermadec Islands.
“The hilly island has been volcanically active in a geologically recent timeframe.”
(More to follow)