UWI seismologist warns more ash likely even as eruption fury eases

Amid signs of waning intensity in the eruptions of the La Soufrière volcano compared to last weekend’s fury, the region’s leading seismologist Friday warned Barbadians that they are far from out of the woods from the ash fallout.

The update came during the Government’s latest press briefing on the twin crises – the state of coronavirus outbreak and Friday’s volcanic eruption amid a national campaign to clear away tonnes of ash from last weekend’s blast.

UWI Seismic Research Centre director Dr Erouscilla Joseph said although the volcano has shown a relative slowdown in explosive eruptions in neighbouring St Vincent, Barbadians should not become complacent, as eruptions can continue for some weeks.

Dr Joseph said: “In terms of the prognosis, we are saying the volcano continues to erupt, although the explosive activity is somewhat diminishing in intensity, that does not mean that it has ended at this time.

“Its current pattern of seismicity [does] indicate there is periodic [signs] of a lava dome, but this has not been confirmed. We hope to see satellite images to help us see how big the dome is growing if there is a dome, but what can happen is that this dome is continually destroyed by explosions, such as the one that happened [Friday] morning.”

Dr Joseph also revealed that tests were also done in the waters of St. Vincent and the Grenadines for Sulphur Dioxide (SO2) flux; this gas is often tested for after major volcanic eruptions to gauge the amount of fresh magma still being able to make it to the surface to cause an eruption.

This, along with other data coming from monitoring stations around the site, points to the volcano going through a form of deflation, and a possible lessening in intensity, according to the UWI seismologist.

She said: “We are also now seeing, a pattern of deflation from the Ground Deformation Stations; that is around the volcano, [and] there are three stations that we have been able to get the data from continuously that is tracking the deflation… “Think of a balloon, when magma comes up and it fills this balloon, it expands, and when the balloon bursts and that magma comes out onto the surface, we get deflation.
“Right now we are seeing the deflation signal, which means that everything that is in there, is trying to get out.”
(RB)