By: Staff Writer
March 12, 2021
Top volcanologist on the ground in St Vincent and the Grenadines (SVG) said that the La Soufriere volcano is still “dangerous” despite it not being explosive at the moment, but it can change “very quickly.”
Roderick Stewart volcano-seismologist from the University of the West Indies (UWI), Seismic Research Centre (SRC) and of the Montserrat Volcano Observatory (MVO), said in a YouTube interview: “At the moment, we’re getting earthquake signals, but they’re all very, very small, and they’re associated with the dome itself, and the indication is that there’s no pressure buildup.”
Noting that this may not be 100 percent accurate, he added: “But if we were moving towards explosive activity, we would expect to see things that indicate that pressure build up and the classic progression would be that we’ll get started getting VT’s (volcano tectonic earthquake), then they move to hybrids, then they’d move to long period, then they’d move to tremor, and then there’s an explosion,” further commenting that this may not happen in this particular sequence.” ,
Volcanic-tectonic earthquakes (VTs) are caused by slip on a fault near a volcano. Volcanoes are often found in areas of crustal weakness and the mass of the volcano its self adds to the regional strain.
First responders to the La Soufriere volcano activity said earlier this year that if the volcano becomes explosive, residents would have less than 48 hours in that event.
Mr Stewart also said for an explosive eruption he expects “some sort,” of change in the activity to show how the pressure at the volcano would be building up.
Mr Stewart is saying now, however: “Ever since the activity started at the beginning of the year, all we’ve really seen are these small seismic signals associated with the dome growth.”
He added: “We’ve only had a handful of VT’s and a handful, there’s not a lot, we would expect to see swarms of hundreds of them. So really, the volcano hasn’t changed what it is doing since it started the dome is slowly growing, and it’s growing quietly. That itself could cause other hazards. But at the moment, there’s no other sort of seismic science going on.”
This is no time to ease up and lose vigilance on the volcano despite it not showing the propensity at this time to become explosive, “volcanoes are dangerous things,” said Mr Stewart. He added: “Things can happen close on the dome with very little warning. If you look at the volcano, like I’m looking, there’s a large amount of vegetation that’s been destroyed by the gases.”
He also said that if something were to happen, it would happen “very quickly,” and then pointed to SVG’s National Emergency Management Organisation (NEMO) had set up special zoning in preparation for a snap explosion of the volcano.
There is hope however as Mr Stewart said that his team ahs “lots of monitoring equipment” and that they are maintaining them well. There are also a lot of technicians in place who have come from Trinidad and Tobago and Montserrat.
Watch the full video interview here: