By Harry Pearl
SYDNEY (Reuters) - An 7.9 magnitude earthquake struck off Papua New Guinea (PNG) on Sunday, triggering a tsunami alert for several Pacific islands though that was subsequently wound back to cover just PNG and the neighboring Solomon Islands.
The United States Geological Survey (USGS) downgraded the quake from an initial measurement of magnitude 8. It struck some 47 kms (29 miles) west of Arawa on the north coast of Bougainville Island at a depth of 154 km (96 miles), USGS reported.
The Pacific Tsunami Warning Center said in an updated advisory that waves of 0.3 to 1 meter above tidal level were possible along the coasts of PNG and the Solomon Islands. It wound back an earlier alert that encompassed Nauru, Pohnpei, Kosrae, Vanuatu, Chuuk and Indonesia.
Quakes are common in Papua New Guinea, which sits on the Pacific's "Ring of Fire", a hotspot for seismic activity due to friction between tectonic plates.
Loti Yates, the director of the Solomon Islands National Disaster Management Office, said people had been told to move to higher ground in Choiseul and Western Province.
"That isn’t the only fear we have," Yates told Reuters by phone from the capital of Honiara, adding that his office was trying to contact communities closest to the quake's epicenter. "We are also worried about damage from the earthquake."
Chris McKee, assistant director at PNG's Geophysical Observatory Office in Port Moresby, said there were no initial reports of damage from near the epicenter of the quake, which is sparsely populated.
"Because of the great depth of the earthquake it is unlikely that there will be any significant tsunami activity," McKee told Reuters.
Australia and New Zealand both said they had assessed the threat and there was no danger to their coastlines.
Bougainville Island is one of the islands that make up the Autonomous Region of Bougainville within Papua New Guinea (PNG) which is home to around 300,000 people.
(Additional reporting by Charlotte Greenfield in WELLINGTON; Writing by Jane Wardell; Editing by Simon Cameron-Moore and Christian Schmollinger)