UWI Seismic unit head: Volcanic activity could last for weeks

VOLCANIC activity at La Soufriere in St Vincent is likely to persist for weeks, but will not last for years like the volcano in Montserrat (which saw eruptions in 1995 and 1997), geologist/vulcanologist Prof Richard Robertson predicted on Tuesday night.

The director of the UWI Seismic Research Centre was participating in a virtual forum discussing the disruption, titled Rally round St Vincent and the Grenadines, broadcast on UWI TV.

He said the April 13 eruption had repeated almost exactly what had happened in an eruption there on the same date in 1979.

Gas-rich magma (molten rock), he said, had oozed out from the volcano and then gained so much energy such that it then virtually exploded, rose up but then collapsed on itself to produce density currents. Pyroclastic density currents are hazardous ground-hugging flows of ash and debris that can travel at speeds of hundreds of metres per second and reach many tens or hundreds of kilometres away.

Robertson said that eruption had followed the same pattern as that of 1979 but was bigger.

"It is doing what the signals tell us it wants to do. You couldn't ask for a more classic eruption. It is not behaving well, because it is erupting, but you could track and follow it. We can do well-constrained forecasts of what it's likely to do." While the volcano might go on "for a little bit longer than expected," Robertson said a substantial part of the island could continue with life. While difficult weeks and months loomed ahead, he hailed Vincentians as "a tough people."

Further, while things seem tough now, the volcano could create opportunities for Vincentians in agriculture and ecotourism. Saying a 1902 eruption at that volcano had been ten times worse than that of 1979, Robertson nonetheless said, 1902 "still allowed a substantial part of the country in the south to go on living."

Otherwise, with ash as a major hazard, he suggested water should now be sought in ground sources, as opposed to surface sources.

Moderator Dr Cleveland Samm asked when things would get back to normal.

Robertson replied the volcano was behaving with such a large degree of uncertainty that any predictions would have a large margin of error, but it was most likely that unrest would last for weeks, but probably not for months. He reckoned that periods of explosion and intense activity will become less likely as time passes but also said no one knows how much magma was below the surface and whether conditions above ground would change.

"I'd be surprised if it shuts down tomorrow or midweek," Robertson said. "You could look forward to next year things back to normal."

On a bright note, he said the ash could be worked into the soil for farming. The ash also held out much potential for the local construction sector, as most building materials used in St Vincent had volcanic origins. The ash could be stockpiled, Robertson said.

UWI vice chancellor Prof Sir Hilary Beckles said UWI had the expertise to help in St Vincent, in numerous aspects. The experts could help assess building damage, examine the impact on sectors such as agriculture and fisheries, and check over the water supply. He said UWI is a premier public Caribbean university whose role it is to help its communities.

UWI pro vice chancellor (global affairs) Dr Luz Longsworth underlined the need for psychosocial counselling for the whole population, especially children, who are particularly traumatised by the eruptions.

"Many little ones do not understand what is happening." She said the mental health of children can be helped through story-telling and the arts.

UWI Open Campus deputy principal Dr Francis Severin said the prevalence of ash in the atmosphere was having a bad effect of the psyche of Vincentian university students, remarking, "I've never seen that before." He said UWI was helping local students such as by providing counselling – "helping us to survive is the feeling that the West Indies is with us," Severin said.