SYDNEY—A strong 6.0-magnitude quake hit off the South Pacific island of Vanuatu on Wednesday, seismologists said, but no tsunami warning was issued.
The US Geological Survey said the tremor at 4:21 a.m. (1721 GMT Tuesday) was 31 kilometers (19 miles) deep and some 84 kilometers south of Lakatoro.
It was 136 kilometers from the capital Port Vila.
The quake came just over half an hour after a shallow 5.9-magnitude tremor struck 94 kilometers from Lakatoro.
The quake at 3:46 a.m. was only three kilometers deep, but no tsunami warning was released.
Earthquakes regularly hit near Vanuatu, with a 6.8-magnitude shaker hitting off the South Pacific island in December without generating a destructive tsunami.
The island lies on the so-called “Pacific Ring of Fire,” a zone of frequent seismic activity caused by friction between shifting tectonic plates.
It has been rocked by several large quakes in recent years, averaging about three magnitude 7.0 or above incidents every year.