A magnitude 6.4 earthquake struck Papua New Guinea at 9:17 a.m. UTC and was felt across the country, the U.S. Geological Survey said. The rupture lay about 64 miles down, roughly 30 miles from the town of Kainantu.
The USGS described the local building stock as a mix of vulnerable and earthquake-resistant structures. It also pointed out that recent quakes in the area have set off landslides and liquefaction, the hazards that tend to follow shaking in this kind of terrain.
A long, restless boundary
The quake came on the Australia-Pacific plate boundary, a fault system about 2,500 miles long that stretches from the Sunda (Java) trench in the west to the Solomon Islands. Papua New Guinea also sits on the Pacific Ring of Fire, where the Pacific Plate meets a ring of neighboring plates.
Roughly 90 percent of the world’s earthquakes and about 75 percent of its active volcanoes occur along that belt. It holds around 452 volcanoes and runs some 25,000 miles in a horseshoe, from the southern tip of South America up the Americas, across Alaska and Russia, then down through Japan, the Philippines, Indonesia, Papua New Guinea and New Zealand.
The country’s record is heavy. Since 1900 it has seen 13 earthquakes of magnitude 7.5 or greater. In April 2007 a magnitude 8.1 quake set off a tsunami that killed at least 40 people, according to the USGS.
