La Soufriere 2021: Recharge, remobilisation or complete renewal of a magmatic system
Lead Research Organisation:
University of Oxford
Department Name: Earth Sciences
Abstract
Volcanic eruptions that form lava domes pose a significant hazard, as they tend to last for extended periods of time (often weeks to months) and can often switch quickly from slow effusion to violent explosion. The start of a new lava dome eruption offers a rare opportunity to carry out a rapid study to understand where the new lavas came from; and to test ideas about how the eruption will progress.
On December 27, 2020, a new lava dome eruption began in the summit crater of the Eastern Caribbean volcano of La Soufriere, on the island of St Vincent, after a short period of unusual seismic activity. The new lava dome has been growing steadily, erupting on to the floor of the summit crater, next to an old lava dome that erupted in 1979. Scientists at the University of the West Indies Seismic Research Centre (SRC) have been monitoring events, and collected some new lava samples on January 16, 2021.
St Vincent had two previous lava-dome eruptions in the 1970s. In 1971-2, a lava-dome formed in the summit crater, which at that time was flooded. After 3-4 months of slow dome growth the eruption ended, and there was no explosive activity. Scientists collected one lava dome sample at the time, and a piece of this is now held in the Smithsonian Institution in the USA. In 1979, a new eruption began with a series of violent explosions, and then switched to a steady lava-dome eruption for the next 5 months.
Our rapid-response study of the newly-erupting lavas on St Vincent will answer the question of where the new magma has come from. There are several possibilities that we anticipate, and our observations will allow us to work out which possibility is the most likely:
- Is this a new batch of magma, which has just risen up into the volcano? And if so, can we understand why?
- Is this a batch of magma that was left over from an earlier eruption, which has been disturbed, and has begun to erupt as a result? And if so, can we understand how the system was disturbed?
In both cases, our findings will feed directly into the continuing investigations by the scientific team in charge of the volcano response, and will help to develop and firm up ideas about what will happen next in the eruption.
On December 27, 2020, a new lava dome eruption began in the summit crater of the Eastern Caribbean volcano of La Soufriere, on the island of St Vincent, after a short period of unusual seismic activity. The new lava dome has been growing steadily, erupting on to the floor of the summit crater, next to an old lava dome that erupted in 1979. Scientists at the University of the West Indies Seismic Research Centre (SRC) have been monitoring events, and collected some new lava samples on January 16, 2021.
St Vincent had two previous lava-dome eruptions in the 1970s. In 1971-2, a lava-dome formed in the summit crater, which at that time was flooded. After 3-4 months of slow dome growth the eruption ended, and there was no explosive activity. Scientists collected one lava dome sample at the time, and a piece of this is now held in the Smithsonian Institution in the USA. In 1979, a new eruption began with a series of violent explosions, and then switched to a steady lava-dome eruption for the next 5 months.
Our rapid-response study of the newly-erupting lavas on St Vincent will answer the question of where the new magma has come from. There are several possibilities that we anticipate, and our observations will allow us to work out which possibility is the most likely:
- Is this a new batch of magma, which has just risen up into the volcano? And if so, can we understand why?
- Is this a batch of magma that was left over from an earlier eruption, which has been disturbed, and has begun to erupt as a result? And if so, can we understand how the system was disturbed?
In both cases, our findings will feed directly into the continuing investigations by the scientific team in charge of the volcano response, and will help to develop and firm up ideas about what will happen next in the eruption.
Publications
Cole P
(2023)
Explosive sequence of La Soufrière, St Vincent, April 2021: insights into drivers and consequences via eruptive products
in Geological Society, London, Special Publications
Frey H
(2023)
Petrology of the explosive deposits from the April 2021 eruption of La Soufrière volcano, St Vincent: a time-series analysis of microlites
in Geological Society, London, Special Publications
Joseph EP
(2022)
Responding to eruptive transitions during the 2020-2021 eruption of La Soufrière volcano, St. Vincent.
in Nature communications
Weber G
(2023)
Petrology of the 2020-21 effusive to explosive eruption of La Soufrière Volcano, St Vincent: insights into plumbing system architecture and magma assembly mechanism
in Geological Society, London, Special Publications
| Description | This award funded the analysis of a small set of samples from the new (2021) lava dome, that were collected during the first few weeks of the eruption by colleagues at the Seismic Research Centre, University of the West Indies. Despite the challenges of lockdowns due to COVID, we were able to process and analyse these lava dome samples using a range of different techniques. We found that their chemical compositions are very similar to the compositions of magmas erupted from the same volcano in 1979; and also similar to the compositions of magmas that were erupted during a later stage of the 2021 eruption, when the activity accelerated and became much more explosive. Subsequently, we have been looking closely at the mineral make-up of these samples, to try and narrow down the conditions under which they formed; and to tease out the small differences between samples from the different phases of eruption. We have written up a paper which summarises this work, and this is currently under review for publication. |
| Exploitation Route | We have completed a research paper on this work, which is now in review, and the samples we have analysed are now being used for follow on work. The samples have also been used for follow-on work by several PhD students and other colleagues, and our ideas are evolving as this work continues. |
| Sectors | Environment |
| Description | Urgency funding provided to the team allowed us to set about characterising samples from an early stage of the 2021 eruption, before the eruption transitioned into an explosive phase of activity. Ongoing work by a wide team of collaborators has helped to advance our understanding of the samples, and opened up new lines of investigation for future research. Our working together on this project has also provided additional stimulus for the co-production of materials and activities for public engagement around volcanic eruptions, volcanic hazards and risk, uncertainty, and scientific decision-making during emerging events. We have sought and obtained follow-on funding for these public engagement activities, and trialled some new hands-on activities at a science festival. |
| First Year Of Impact | 2023 |
| Sector | Culture, Heritage, Museums and Collections |
| Impact Types | Societal |
| Description | Continuing collaborations with the Seismic Research Centre, University of the West Indies |
| Organisation | University of West Indies |
| Department | Seismic Research Centre |
| Country | Trinidad and Tobago |
| Sector | Academic/University |
| PI Contribution | We continue to work together on elements of the volcanic activity of the La Soufriere volcano, on St Vincent. |
| Collaborator Contribution | Collaboration, sharing of ideas, co-production of papers and reports and sharing of samples. |
| Impact | Multiple papers from earlier phases of the collaboration; one new joint paper on the 2021 eruption. |
| Start Year | 2012 |
| Description | Christmas STEM lecture |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Schools |
| Results and Impact | 30 minute lecture on volcanoes and volcanic activity, followed by 1 hour interactive and hands-on workshop led by students and researchers, which was run for local school groups (Year 9). The audience was 150. The activity was used to provide training for three undergraduate volunteers who had no previous public engagement experience; and opportunities for more senior researchers (PhD students and post-docs) to develop their engagement skills, and to lead on a set of different activities. The level of engagement was impressive, given the concerns around COVID. We expect to get more complete evaluation data in the next few weeks. |
| Year(s) Of Engagement Activity | 2021 |
| Description | Norwich Science Festival 2023 |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Creative and engaging hands-on activities and demonstrations around volcanoes, volcanic activity and uncertainty, developed by a multi-institution team led by Prof Jenni Barclay. |
| Year(s) Of Engagement Activity | 2023 |
| Description | School activities and science fairs (Oxford) |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Schools |
| Results and Impact | We have a set of engaging and hands-on activities around volcanoes and volcanic activity which we us regularly to engage with primary-school groups, and as demonstrations at science fairs and open days. In 2023, we ran a version of this at the 'Volcano Day' in the Natural History Museum, London as a part of an ongoing collaboration with colleagues at University of East Anglia. |
| Year(s) Of Engagement Activity | 2021,2022,2023 |