Reconstructing magma storage and transport prior to giant Icelandic fissure eruptions
Lead Research Organisation:
University of Cambridge
Department Name: Earth Sciences
Abstract
The recent eruption of the Eyjafjallajokull volcano in southern Iceland has had a significant impact on the UK. The ash cloud severely disrupted European aviation in April and May of 2010 leading to a loss of over $4 billion to global economic productivity. This eruption is, however, relatively small compared to that of many other Icelandic volcanoes. In 1783 AD, the eruption of the Laki volcano produced about 15 cubic kilometres of lava and ash in less than a year - about 100 times larger than the present Eyjafjallajokull event. The effects of the Laki eruption were devastating. Ash fell in the UK, and huge quantities of noxious fumes were released to the atmosphere. This volcanic gas release was catastrophic for the Icelandic population. Hydrogen fluoride gas was particularly damaging: people and livestock developed fluorosis, which deforms the bones. The combination of fluorosis and the associated famine contributed to the death of 21% of the Icelandic population. The Laki eruption also released large quantities of sulphur in volcanic gases, and this sulphur spread in a deadly dry fog over Europe and North America, which led to extreme climatic variability over the following 3 years, including a severely cold winter in Europe and North America in 1784. This extreme weather combined with the respiratory impact of the volcanic gases to cause a 25% increase in death rate in Britain and France. If an eruption like Laki were to take place today, the negative impacts on economic activity and human health would be significant. In addition to the dangers discussed above, volcanic ash would present dangers to aviation. It is likely that an eruption similar to Laki will take place in the next few centuries, if not decades. Recorded history in Iceland stretches back 1200 years, and in this time 5 giant eruptions have occurred, with Laki being the youngest of these eruptions. Given the possibility of a similar devastating eruption in the foreseeable future, it is important that understanding of the processes operating before such eruptions is used to develop forecasting and risk management strategies. Volcanic monitoring is based on observation of earthquake activity and swelling of the earth surface and gas release as magma shifts in the plumbing system of the volcano. Successful forecasting is dependent on identifying the fingerprint of rising magma prior to the eruption. Eruptions like Laki have not taken place since the development of modern monitoring techniques. Therefore we need to use the composition of the lava and ash released during the eruption to reconstruct the evolution of the magma as it rose through the crust before eruption. We will examine the compositions of melt inclusions, microscopic pockets of melt that are trapped as crystals grow in magma chambers in the crust, using state-of-the-art scientific instruments. We will use the composition of the inclusions and their host crystals to determine the rate at which gas forms from magma as it is stored in the crust. These observations will allow us to track the history of magma storage and ascent before the eruption starts. These models of pre-eruptive magma movement will be used to predict the fingerprint of magma rising before large basaltic eruptions, a fingerprint that might be recognised by volcano monitoring strategies. This forensic study of the products of the Laki event will lead to improvement in our ability to forecast the onset of catastrophic basaltic eruptions. Our study also has implications for the understanding of giant eruptions in the past, where millions of cubic kilometres of lava have been produced in short intervals of geological time. Such events have been linked to extreme environmental change, rapid global warming and mass extinction of species. Our approach will allow for improved measurement of the release of environmentally significant volcanic gases from these giant eruptions.
Organisations
Publications
Hartley M
(2015)
Diffusive over-hydration of olivine-hosted melt inclusions
in Earth and Planetary Science Letters
Hartley M
(2014)
Reconstructing the deep CO2 degassing behaviour of large basaltic fissure eruptions
in Earth and Planetary Science Letters
Hartley M
(2016)
Tracking timescales of short-term precursors to large basaltic fissure eruptions through Fe-Mg diffusion in olivine
in Earth and Planetary Science Letters
Maclennan J
(2017)
Bubble formation and decrepitation control the CO 2 content of olivine-hosted melt inclusions
in Geochemistry, Geophysics, Geosystems
Mutch E
(2019)
Rapid transcrustal magma movement under Iceland
in Nature Geoscience
Mutch E
(2019)
Rapid transcrustal magma movement under Iceland
Neave D
(2014)
Crystal Storage and Transfer in Basaltic Systems: the Skuggafjöll Eruption, Iceland
in Journal of Petrology
Neave D
(2015)
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash)
in Contributions to Mineralogy and Petrology
Neave D
(2013)
Crystal-Melt Relationships and the Record of Deep Mixing and Crystallization in the ad 1783 Laki Eruption, Iceland
in Journal of Petrology
Neave D
(2017)
Volatile and light lithophile elements in high-anorthite plagioclase-hosted melt inclusions from Iceland
in Geochimica et Cosmochimica Acta
Neave D
(2014)
Melt mixing causes negative correlation of trace element enrichment and CO2 content prior to an Icelandic eruption
in Earth and Planetary Science Letters
Passmore E
(2012)
Mush Disaggregation in Basaltic Magma Chambers: Evidence from the ad 1783 Laki Eruption
in Journal of Petrology
Thomson A
(2013)
The Distribution of Olivine Compositions in Icelandic Basalts and Picrites
in Journal of Petrology
White R
(2019)
Melt movement through the Icelandic crust.
White RS
(2019)
Melt movement through the Icelandic crust.
in Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
Description | We have collected a large number of samples from the products of the gigantic AD 1783 eruption of the Laki volcano in south Iceland. We have used microanalysis to determine the composition of pockets of melt trapped in crystals carried by this lava. These melt pockets have been used to determine the depth of storage and crystallisation of magma in the lead-up to this large eruption (<20 km). We have been able to record the progressive degassing of the magma and have calculated the total amount of CO2 released from the magma as it rose to the surface before eruption (304 Mt). We will soon be able to establish the timescales over which this gas was released and determine if it could be a useful monitoring tool. We have also found that rapid overturn and mixing of crystals and magma took place at shallow levels <100 days before eruption. |
Exploitation Route | Our constraints on the depths of magma chambers that feed large eruptions on Iceland is useful for interpreting volcano monitoring results. We also hope that our estimates of pre-eruptive volcanic CO2 flux might be used to develop new volcanic monitoring tools. We have set up a link with Icelandic volcano hazard network and will provide our results to these researchers and public servants. We have set up links with the volcanology unit of BGS and the leaders of the FUTUREVOLC consortium. We have disseminated these findings at international (AGU) and UK (VMSG) conferences and have 1 publication accepted pending revision and 3 more in an advanced state of preparation. |
Sectors | Environment |
Description | Energy companies interested in magmatic carbon budgets. We have developed techniques and conceptual understanding. |
First Year Of Impact | 2015 |
Sector | Energy |
Impact Types | Economic |
Description | Royal Society International Exchange |
Amount | £3,000 (GBP) |
Funding ID | IE150300 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 07/2015 |
End | 10/2015 |
Description | Unlocking the C and N budget of the Earth |
Amount | £437,287 (GBP) |
Funding ID | NE/V011383/1 |
Organisation | Natural Environment Research Council |
Sector | Public |
Country | United Kingdom |
Start | 11/2021 |
End | 04/2024 |
Description | Geological Society London Lecture |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | The Geological Society oragnises a series of public lectures in their London headquarters. I provided one of these events, talking to a full lecture theatre twice in a day. |
Year(s) Of Engagement Activity | 2015 |
URL | https://www.geolsoc.org.uk/Events/Past-Meeting-Resources/London-Lectures/London-Lectures-2015/Hidden... |
Description | Magazine Article - Intelligent Life - on geological map of Iceland |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Wrote a piece on the development of the Geological Map of Iceland for Intelligent Life. This is a magazine with global outreach, part of the Economist group. |
Year(s) Of Engagement Activity | 2015 |
URL | https://www.1843magazine.com/content/places/john-maclennan/underneath-ash-clouds |
Description | Petrological constraints on deep degassing prior to large basaltic fissure eruptions: CO2 in Laki melt inclusions |
Form Of Engagement Activity | Scientific meeting (conference/symposium etc.) |
Part Of Official Scheme? | No |
Type Of Presentation | paper presentation |
Geographic Reach | International |
Primary Audience | Other academic audiences (collaborators, peers etc.) |
Results and Impact | Oral presentation at International Conference - AGU, San Francisco, 2012 Useful feedback. Employment offers for PDRA. |
Year(s) Of Engagement Activity | 2012 |
Description | Petrological constraints on deep degassing prior to large basaltic fissure eruptions: CO2 in Laki melt inclusions |
Form Of Engagement Activity | Scientific meeting (conference/symposium etc.) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | |
Results and Impact | Poster at Volcanic and Magmatic Studies Group meeting in Bristol, January 2013 |
Year(s) Of Engagement Activity | 2013 |
Description | Tracking pre-eruptive degassing at Laki, Iceland, through diffusion modelling |
Form Of Engagement Activity | Scientific meeting (conference/symposium etc.) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Participants in your research or patient groups |
Results and Impact | Presentation at the IAVCEI conference, Kagoshima, Japan, 2013 |
Year(s) Of Engagement Activity | 2013 |
Description | Tracking short-term precursors to large basaltic fissure eruptions through diffusion modelling |
Form Of Engagement Activity | Scientific meeting (conference/symposium etc.) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | |
Results and Impact | Presentation at Volcanic and Magmatic Studies Group Meeting in Edinburgh, January 2014. |
Year(s) Of Engagement Activity | 2014 |