The quake was felt at 3.45 a.m. local time.
The area lies along an natural disaster zone known as the Papuan Fold Belt, which is the fault responsible for the mountain range that forms the spine of the nation, he said.
The United States Geological Survey (USGS) said the quake hit about 90 kilometres south-west of Porgera in the early hours of this morning at a depth of 35 kilometres. A series of aftershocks were also registered, the company added.
At this stage there have been no fatalities reported in the township of around 50,000 people, however Don Blakeman from the U.S. Geological Survey told media that significant damage was very likely. More concerning was any heavy masonry used in industrial construction, he said.
Canada's halftime report card at the Pyeongchang Winter Olympics
Parsons, who finished just two hundredths off silver, was nevertheless ecstatic after claiming Britain's first medal of the Games. Contending for the top of the overall medal table was the stated goal by the Canadian Olympic Committee.
The quake was not expected to generate a tsunami, the Pacific Tsunami Warning Centre said.
ExxonMobil Corp said it had shut its Hides gas conditioning plant, close to the quake's epicenter, to assess if there was any damage. "ExxonMobil PNG has confirmed that the PNG LNG facility at Hides has also been safely shut down".
Papua New Ginuea rests on the so-called "Ring of Fire" - a hotbed of seismic activity surrounding a tectonic plate that spans the pacific.