Live Updates: La Soufrière Volcano Situation Overview

Present La Soufrière Alert Level:ORANGEThere is a highly elevated level of seismic and/or fumarolic activity or other unusual activity. An eruption may begin with less than twenty-four hours' notice.

Key Messages:
The Eruption: An effusive eruption is ongoing at the La Soufrière Volcano. Lava is confined to the crater at this time. Steam and volcanic gases can be seen above the crater, with acidic gases damaging nearby vegetation. New cracks have formed on the crater floor and the 1979 pre-existing dome. The new dome could overtop the crater and send lava cascading down the volcano in the coming months if the ongoing rate of effusion continues.
Seismicity: There is little seismicity associated with the ongoing eruption. Rockfalls have been detected by the new seismic stations.
The Alert Level: The alert level is at Orange. An eruption may begin with less than 24 hours’ notice. Persons living in areas close to the volcano which include communities from Fancy to Georgetown and Belle Isle to Richmond are asked to remain alert and listen to all advisories from the National Emergency Management Organisation (NEMO).
No evacuation order has been issued for any communities of St. Vincent.
— The public is advised to desist from visiting the volcano and do not interfere with monitoring equipment.
— Official information will originate from St. Vincent and the Grenadines National Emergency Management Organization and the University of the West Indies Seismic Research Center. FAQ‘s have also been addressed by authorities.

The Eruption – How did we get here?

Last updated: 8:00 PM January 16th, 2021

An effusive eruption is ongoing within the crater of the La Soufrière Volcano, with a new dome forming that continues to grow in size. Activity remains confined within the crater at this time. Steam can be observed above the crater, with strong gas emissions ongoing. Those living near the volcano can expect strong sulfur smells over the next several days to weeks. Acidic gases have affected vegetation. There is the possibility of the new dome overtopping the crater rim in the coming months. New cracks have formed on the crater floor and the 1979 pre-existing dome.

According to the University of the West Indies Seismic Research Centre‘s Director, Dr. Erouscilla Joseph, beginning in early November, there was an increase in the background level of seismicity at the La Soufrière Volcano.

NASA FIRMS Showing the La Soufrière eruption hotspot evolving since the initial eruption. (NASA/FIRMS/ESDID/VIIRS/MODIS)
NASA FIRMS Showing the La Soufrière eruption hotspot evolving since the initial eruption. (NASA/FIRMS/ESDID/VIIRS/MODIS)

At 1:20 PM on December 27th, 2020, a UWI SRC staff member was made aware of a hotspot being detected on a NASA satellite used to track wildfires globally. The hotspot, near the center of the crater, was detected by NASA’s MODIS and VIIRS satellites used for Fire Information for Resource Management System.

Small satellite dome in the crater of the La Soufrière Volcano as fresh magma made its way to the surface of the volcano on December 29th, 2020. (Kemron Alexander/Soufriere Monitoring Unit)
Small satellite dome in the crater of the La Soufrière Volcano as fresh magma made its way to the surface of the volcano on December 29th, 2020. (Kemron Alexander/Soufriere Monitoring Unit)

The hotspot has persisted. Upon routine, visible inspection by the Soufrière Monitoring Unit, the team confirmed the hotspot in the crater, with satellite imagery on the 29th of December showing an extension of the hotspot.

As the team was preparing to make another visible inspection, reports came in from Rose Hall, St. Vincent of greyish-white emissions above La Soufrière’s crater.

An effusive eruption was confirmed within the crater of the La Soufrière Volcano, with a new satellite dome forming that continues to grow in size.

An effusive eruption occurs when molten rock (lava) reaches the Earth’s surface and erupts passively. The products of these eruptions are lava flows and lava domes. They generally occur when the gas content of the magma is low.

Effusive vs explosive eruption explained by the UWI SRC. (UWI SRC/NEMO)
Effusive vs explosive eruption explained by the UWI SRC. (UWI SRC/NEMO)

The new dome has formed southeast of the existing dome. Strong gas emissions have been reported and the small crater lake that previously existed has dried. Magma continues to ooze to the surface since the eruption began.

NEMO has advised when the magma interacts with the surface temperature, especially during the mornings when the air is cool, it appears as steam which may be seen above the crater. Similar activities may continue for weeks or months.

In addition, with strong gas emissions, people living in areas close to the volcano should expect strong sulfur smells for several days to weeks, depending on changes in wind direction.

In addition, gas emissions have been observed from several areas of the 1979 done, as well as the crater floor through several new cracks which have developed, in addition to gas emissions from the new lava dome.

Acidic gases continue to affect the nearby vegetation, with extensive damage observed within the eastern, southern, and western parts of the inner crater walls. The damage reported on previously that is occurring along the upper part of the south western crater rim, has continued to slowly extend downslope.

Burnt vegetation within the crater of the La Soufrière Volcano, St Vincent as acidic gases affect the area. (UWI SRC/Richard Robertson)

This effusive eruption could overtop the crater and send molten lava cascading down the volcano in the coming months if the ongoing rate of effusion continues. Dr. Erouscilla Joseph of the UWI Seismic Research Center explained, “there is a little lip on the crater and where the dome is growing. It is close to that lip. If the volume of material is large enough to spill over that lip, there is the potential for the material to flow down the flacks of the volcano and then, of course, affect people.”

Compilation of the La Soufrière Dome since eruption to present. (All images courtesy UWI SRC/NEMO)
Compilation of the La Soufrière Dome since eruption to present. (All images courtesy UWI SRC/NEMO)

Based on very crude data from aerial reconnaissance, the UWI SRC estimates that 700,000 cubic meters of magma have erupted as of January 4th, 2021. Joseph stressed the estimate’s uncertainty, but it will take approximately six and a half months to cross the crater rim if the current effusion rate continues. However, the La Soufriere volcano is a dynamic system and changes daily.

New observations have discovered the new La Soufrière volcano is now about three-quarter (3/4) the height of the pre-existing 1979 dome. Growth of the dome continues with the lateral spreading of the material towards the east and west in the “moat” areas of the existing 1979 dome. As of January 16th, 2021, the new dome is 340 meters long, 160 meters wide and 90 meters tall.

Seismicity

Last updated: 8:00 PM January 16th, 2021

As of January 1st, the director of the SRC confirmed that there is still no change in the minimal seismicity associated with the new dome in the crater of the La Soufrière Volcano. Rockfalls have been detected with the new seismic stations installed.

Beginning 1st November 2020, the Seismic Research Centre (SRC) at the University of the West Indies recorded 121 seismic events at La Soufriere, with one or two earthquakes a day and a maximum of eleven volcanic earthquakes recorded on 16th November 2020. Two of the earthquakes recorded to date have been larger than magnitude 2.0, at magnitude 2.3 and 2.5, which occurred on 12th and 14th December. The largest so far, at magnitude 3.3, was recorded at 10:29 PM on 16th December 2020.

The Alert Level & Evacuation Orders

Last updated: 8:00 PM January 16th, 2021

There are no evacuation orders in effect for St. Vincent and the Grenadines. The alert level was raised to Orange on December 29th, 2020, and remains at that level to date.

La Soufrière Volcano's Integrated Volcanic Hazard Map for St. Vincent. (UWI SRC/NEMO)
La Soufrière Volcano’s Integrated Volcanic Hazard Map for St. Vincent. (UWI SRC/NEMO)

According to the National Emergency Management Organization, there are no evacuation orders or notices for St. Vincent at this time

The UWI SRC has advised that, based on the complex patterns of previous eruptions, it is too early to conclude that the current activity will remain a simple dome extrusion event. There is still a possibility of a shift to an explosive phase. A definitive prognosis on the current unrest episode cannot be provided until further data analysis is completed.

The alert level remains at Orange. Persons living in areas close to the volcano which include communities from Fancy to Georgetown and Belle Isle to Richmond are asked to remain alert and listen to all advisories from the National Emergency Management Organisation.

La Soufrière Volcano's Alert Level is at Orange. (UWI SRC/NEMO)
La Soufrière Volcano’s Alert Level is at Orange. (UWI SRC/NEMO)

The Official Response

Last updated: 8:00 PM January 16th, 2021

CDEMA’s coordination for support to St. Vincent and the Grenadines, as outlined in their third situation report.

Regular aerial reconnaissance continues, up to two flights a day, safety permitting. A three-person team of scientists from the UWI SRC is present on the island. The team comprises Geologist Professor Richard Robertson, Instrumentation Engineer Lloyd Lynch, and Engineering Technician Ian Juman. Equipment brought from Trinidad has been deployed by the Soufriere Monitoring Unit. Additional personnel joined from the Montserrat Volcano Observatory, Dr Thomas Christopher and Dr Adam Stinton.

UWI Seismic Research Centre Deploys Scientific Team to St. Vincent. A three-person team from The UWI Seismic Research…

Posted by UWI Seismic Research Centre on Thursday, December 31, 2020

Collaboration amongst regional governments, national disaster offices, and CDEMA are ongoing with the Regional Coordination Plan and Regional Coordinating Centre activated.

The CARICOM Disaster Assessment and Coordination (CDAC), CARICOM Operational Support Team (COST), Rapid Needs Assessment Team (RNAT), and Caribbean Disaster Relief Unit (CDRU) have been placed on alert.

Frequently Asked Questions

What hazards are associated with the La Soufrière Volcano?

Particularly with the La Soufrière Volcano, pyroclastic flows and surges, mudflows, ashfall, and projectiles are the most hazardous events expected compared to lava flows, atmospheric phenomena, earthquakes, and phreatic explosions. Secondary effects such as landslides and events of more remote possibility such as directed blasts and structural collapse are also possible.

You can read more about the hazards here.

Know your volcanic hazards. First up: Ash. Let’s be #VolcanoREADY NEMO St. Vincent and the Grenadines

Posted by UWI Seismic Research Centre on Friday, January 1, 2021

Are all volcanoes in the Caribbean connected?

No. The process of subduction across the Lesser Antilles has created the islands north of T&T (with the exception of Barbados) through volcanism, but that’s where the link stops. Seismicity associated with different volcanoes is not linked. Hence, an eruption of La Soufrière does not mean an eruption of Kick’em Jenny or any other Lesser Antilles volcano is imminent. If one occurs, it will likely be an unlucky coincidence.

The SRC is responsible for monitoring all seismic and all volcanological hazards across the English-speaking islands of the Eastern Caribbean. Presently, the ongoing seismic unrest in Dominica is returning to background levels. There are occasional volcanic-tectonic quakes in St. Lucia.

Are the volcanoes all connected? No. Let’s learn why. NEMO St. Vincent and the Grenadines #volcano #lasoufriere #svg

Posted by UWI Seismic Research Centre on Friday, January 1, 2021

Is La Soufrière a threat to T&T?

There is no threat to T&T and the remainder of the Lesser Antilles, with the obvious exception at this time being St. Vincent.

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