The minor earthquakes, which struck on Sunday, were recorded at a seismograph station more than 75 kilometres from the mining village.

The strongest, measuring 2.2 on the Richter scale, struck about 8.45pm.

It shook houses in the village, waking residents.

"I was nearly thrown out of bed," resident Deidre Olofsson said.

"It was absolutely frightening, I have never been so scared."

The tremors add to another 51 Hunter earthquakes in the past 20 years, prompting questions over whether they are linked to the region's booming mining industry.

With magnitudes up to 5.3, the quakes were recorded at Geoscience Australia, a government agency in Canberra.

A map plotting their locations show the vast majority of tremors occurred in the heart of the Hunter's mining country near Cessnock, Muswellbrook and Dungog.

The largest was at Ellalong on August 6, 1994, which was the biggest quake in the region since Newcastle's 1989 earthquake.

John Polglase, a geologist from Bundella, west of Murrurundi, said mining-induced seismic activity had been well documented worldwide, and blasting or a longwall mining method called "top caving" could be associated with Hunter quakes.

"Nature has flaws and compressed and folded strata have weaknesses. If you do any blasting or mining you can activate those flaws and cause local movements of rock," he said.

"Some of the earthquakes could be due to blasting, and some can be due to faults and fractures and fissures shifting due to loading or unloading of the strata. You can even get rock readjustment from large coal train movements."

Mr Polglase said the "cluster of middle-order shocks" in the Hunter indicated a need to investigate the tremors and confirm their cause.

"A longwall mining collapse or quarry explosions can be quite measurable," he said.

But the NSW Minerals Council has ruled out a study to investigate the supposed link between the Hunter's mining industry and earthquakes.

"This issue was raised in 2007 and the experts ruled out a link between mining and seismic activity then," a NSW Minerals Council spokesman said.

Geoscience Australia seismologist David Jepsen said there was no evidence to prove or disprove earthquakes were linked to mining.

Mr Polglase said conflicting theories would remain until seismometers were strategically placed in the region to deliver more accurate data about seismic activity.

"Until we get independent observers using the right equipment in the right locations we cannot make dogmatic statements," he said.