(Adds comment from geologist, detail)
SYDNEY, April 11 (Reuters) - A major earthquake with a magnitude of 7.3 was recorded off Papua New Guinea's remote Bougainville Island, the U.S. Geological Survey said on Friday, but there were no immediate reports of damage.
The Pacific Tsunami Warning Centre said a destructive widespread tsunami was not expected but said waves could be generated along coasts in the area from an earthquake of that magnitude.
"This is a highly active area seismically," said Chris McKee, the assistant director at the Port Moresby Geophysical Observatory in the Papua New Guinea capital. "The population is strung out along the coast in a number of centres, but it's not densely populated."
The quake was initially measured at 7.4 but was later revised down to 7.3. It was centred in the sea about 75 km (45 miles) southwest of the town of Arawa on Bougainville, at a depth of about 50 km (30 miles), the USGS said.
In 1998, a magnitude 7 earthquake triggered a tsunami that smashed into villages near Aitape on Papua New Guinea's north coast and killed more than 2,000 people.
Resource-rich Bougainville, which neighbours the Solomon Islands, fought for a bloody war for independence from Papua New Guinea in the 1990s, leading to the closure of the Panguna copper mine, majority-owned by Rio Tinto Ltd
Residents in Bougainville's second-largest town of Buka and Gizo in the north of the Solomon Islands reported feeling tremors but said there was no immediate signs of any damage.
(Reporting By Lincoln Feast and Matt Siegel; Editing by Paul Tait and Robert Birsel)