No increased activity at La Soufriere volcano
THERE IS no increased activity at La Soufriere as has been suggested by some persons this week on radio and social media.
That reassurance came on Wednesday from lead scientist at the University of the West Indies Seismic Research Unit (UWI-SRC) Dr Thomas Christopher.
Christopher has taken over the local monitoring from volcanologist Professor Richard Robertson, and said on a Facebook live discussion on Round Table Talk aired by VC3, that La Soufriere has not been doing anything different than when it started erupting effusively in December.
“We had a look at that dome on Monday and what we noticed was that the northern part of the dome had a lower gradient than the southern part so it seems to be more elongated in the northern part of the dome or in the northern region where it is growing,” Christopher revealed.
He said the volcano is continuing to extrude material which is growing the dome.
He noted that the old dome and the crater wall form a buttress so what has happened is that the rate at which the new dome has grown upwards has fallen away and now it is growing “more” sideways.
Christopher also said new “very useful” gas observations have been made.
“We saw for the first time since I have been here sulphur dioxide in the emissions which we knew should have been there but we weren’t seeing.
“We suspected that it was a function of the ground water interacting with the sulphur dioxide and hiding it from us, so what we think is happening is that there is less ground water now to interact with the sulphur dioxide so we are actually seeing it, so we think the system is drying out,” the scientist said.
He said the system drying out does not change what the volcano is doing, but in terms of monitoring it gives them another tool.
“If we can monitor the SO2 (sulphur dioxide), I think it is much more useful than no SO2 and it is also a technique that does not require you to go onto the crater rim, so it’s not as dangerous as the multi gas technique which we are currently employing now, because we need to get close.
“So it’s safer for the person who is doing it and it is also an added tool to the complement of monitoring techniques,” Christopher explained to viewers.
He is reassuring persons that rumors of increased activity are fake.
“From the data streams we have been getting, because we can look at the seismometers here in real time and we can look at the cameras in real time that we got on the crater, we have not seen any evidence of such an increase,” Christopher said.
He believes that what persons might have noticed is excessive degassing, but degassing is a function of the weather conditions.
“So if there is a lot more moisture or water vapour in the atmosphere you would see a much more thicker plume than if it was a dry atmosphere and today (Wednesday) was a fairly wet day, so they saw the interaction of the gas plume with the atmospheric water and that is not the volcano giving trouble,” Christopher reassured.