Volcanic activity appears to be the cause of the earthquakes 150 kilometres southwest of Prince George, volcanologist Catherine Hickson said Wednesday, but is stressing that the potential for an actual eruption remains low.

Scientists are continuing to monitor the situation and five seismographs have been moved into the location about 20 km. west of Nazko Cone, a small dormant volcano that last erupted 7,200 years ago.

Attention was first drawn to the area, which is about 100 kilometres west of Quesnel, when a series of eight earthquakes, the largest reaching 2.7 on the Richter scale, were recorded over a 48-hour period by two existing seismograph stations about 50 km. away.

Since then the intensity has leveled off to an ongoing series of "microquakes" in the range of 1.0 to 1.5 and occurring at a rate of 50 to 60 per day.

A group of experts -- some from the U.S. Geological Survey and the University of Washington -- met Tuesday to look at the data collected so far and agreed magma, or liquid rock, is intruding deep in the earth's crust in the general region of Nazko.

Hickson described the current activity, estimated to be 25 km. below the earth's surface, as a "simmer." As more magma moves into the spot, the magnitude recorded will increase and reach as high as 4.0, which are often felt but rarely cause damage.

"And if we ever get to the point where we actually have an eruption, we're not expecting anything big," Hickson said. "What we're expecting is similar to what you see in Hawaii -- fire fountains that produce a small cinder cone and some lava flows and things like that.

"The impact would be relatively limited, an area of five or 10 kilometres around where the eruption occurs. There could be gases and ashes that would drift further away, a few tens of kilometres, but relatively low impact."

More specific information will be sent out should the activity escalate, said Hickson, who is preparing a "hazard map" for the area based on what is known about the Nazko Cone. According to the GSC's catalogue of Canadian volcanoes, explosive eruptions produced by Nazko Cone were relatively small but charcoal found in its vicinity suggest forest fires may have been started.

"We want to be proactive," Hickson said. "The likelihood of this becoming an eruption is extremely low, we want to stress that, but we want to be prepared."