Associate Professor Bernie Joyce, who made headlines across Australia last week when he claimed a large volcanic eruption in Victoria was "well overdue", said while volcanoes such as Mt Warrenheip and Mt Buninyong were

extinct, a new volcano could arise among the region's volcano clusters.

"It could still be thousands of years away, but you should expect it to happen," he said.

"Because the ones in the Ballarat area are not as young as (those) in far western Victoria and Mt Gambier, you could expect a new volcano to come up in a cluster."

Prof Joyce said given the potential for volcanic activity, emergency authorities must better prepare themselves and the community to respond to it.

There are about 400 extinct volcanoes across the state.

Around the Ballarat region, volcanoes include Mt Blackwood near Bacchus Marsh, Mt Franklin near Daylesford, Mt Buninyong, Mt Warrenheip and Mt Moorookyle, near Smeaton.

Mt Kooroocheang, north-east of Creswick, stands at 230m and is one of the largest volcanoes in central Victoria.

Mt Warrenheip erupted a million years ago, while Mt Franklin, considered a young volcano, erupted 470,000 years ago.

Prof Joyce said a new volcano was most likely to pop up where there had been eruptions in recent geological times, such as near Camperdown or Hamilton.

Volcanic activity could be a short-lived eruption and could come up "very fast and explosive" with groundwater.

"This happened years ago with (Mt) Warrenheip," Prof Joyce said.

He said it was important for scientists to keep studying volcanoes and dating them, while the government should have scenarios in place for eruptions.

"All volcanoes in Australia are extinct, so we are looking for a totally new volcano, rather than one of the others waking up," he said.