Rift volcanism: past, present and future

Lead Research Organisation: University of Oxford
Department Name: Earth Sciences

Abstract

Early explorers called it Africa's Great Rift Valley, a narrow strip that runs for thousands of kilometres from Djibouti to Mozambique and is perhaps most famous for the vast herds of the Serengeti, mountain gorillas and dramatic landscapes of high peaks and fertile plains. The mountains and valleys are the signs of a continent slowly tearing apart. Moving apart more slowly than your finger nails grow, the African continent will one day split into two, creating a new ocean. As the Earth's crust stretches and thins - like plasticine when you pull it - rocks melt, and the resulting magma rises to the surface. The resultant eruptions have had a dramatic and varied impact on the landscape: great lakes have filled the holes left by enormous eruptions; eruptions of volcanic glass have created a chain of peaks, and wide fields are filled with scattered cones and lava flows. This volcanic landscape is hazardous - a recent report for the World Bank ranked 49 of Ethiopia's 65 volcanoes in the highest category of hazard uncertainty. The high temperatures associated with magma in the Rift Valley make it a rich source of carbon-neutral geothermal power. Multi-billion dollar investments by development agencies are driving a ten-fold expansion in the geothermal infrastructure in East Africa over the next decade.

However, the majority of scientific research has focussed on volcanoes in other tectonic settings, such as Hawaii and Japan, leaving the volcanoes of the East African Rift largely a mystery. For many of them, we can't even say when the last eruption look place and there is no monitoring equipment to detect the early stages of an upcoming eruption. The eruption of Nabro volcano in 2011 was a timely reminder of the potential threats. Situated on the frontier between Ethiopia and Eritrea, the area is remote and sparsely populated, yet the eruption caused 32 fatalities, displaced >5000 people and disrupted regional aviation. Had this eruption originated from one of other 29 volcanoes with the same perceived hazard, but in densely-populated central Ethiopia, the humanitarian and societal cost would have been considerable.

RiftVolc will focus on the volcanoes of the Main Ethiopian Rift in central Ethiopia. The aim is to understand their past behaviour, look for subtle signs of present-day activity and assess the threat posed to the infrastructure and people on and around them. RiftVolc will involve scientists from many disciplines working together to produce an integrated view of the past, present and future of the volcanoes in this region and compare it to other parts of East Africa and volcanoes elsewhere. Together we will spend several months out in Ethiopia, collecting samples, mapping the geology and deploying geophysical instruments, before returning to the lab to use analyse the data and create computer models of the results. Petrologists and geochemists will look at the lavas and ash to figure out the timing, size and style of past eruptions. Geophysicists will look for tiny earthquakes, changes in gravity, the passage of electrical currents and movements of the Earth's surface to understand the plumbing system feeding the volcanoes today. Finally, experts in hazard assessment will model possible scenarios and create a long-range eruption forecast for Ethiopia. We will work with our colleagues in the University of Addis Ababa and the Geological Survey of Ethiopia to ensure our findings are appropriate communicated to the government, industry and people of Ethiopia and with international groups such as the Global Volcano Model to communicate our results to development agencies such as the UN and the World Bank.

Planned Impact

Beneficiaries
National Government (Devolved Government & Government Agencies)
- The Institute of Geophysics, Space Science and Astronomy (IGSSA) at Addis Ababa University is the national organisation providing geophysical monitoring data and advice during unrest and eruptions, and the School of Earth Sciences advises on the character of past eruptions. There are no trained volcanologists in Ethiopia so they collectively provide scientific advice to the Ministry of Agriculture's Disaster Risk Management and Food Security Sector (DRMFSS), the Civil Aviation Authority and Ethiopian Pilots Association during an eruption.
- The Geological Survey of Ethiopia's geoscience data, advice and services contributes to the sustainable development of the agricultural, industrial, infrastructure and other sectors of the Ethiopian economy.
International Organisations and Agencies.
- The IAVCEI Commission on Hazards and Risk links academic research to decision-makers, to reduce the impact of volcanic hazards.
- The Global Volcano Model (GVM) is an international network creating an information platform on volcanic hazard and risk, and is responsible for the volcano component of the biennial UN Global Assessment Report on Disaster Risk Reduction.
Commercial Sector (Public and Private Geothermal Energy)
- Reykjavik Geothermal Limited develops high enthalpy geothermal resources and will construct Africa's largest (1 GW, $4billion) geothermal power plant in our study area.
- Ethiopian Electrical Power Corporation (EEPCO) currently operates a 7MW geothermal power station in our study area, which they are expanding to 70MW.

We will deliver benefit by:
National Government
- Assist Ethiopian scientific partners to build institutional capacity and a volcano monitoring strategy for observations of, and response to, future unrest and eruptions based on information on past eruptions, the processes driving current unrest, and priorities for potential impacts. Enable IGSSA to establish real-time seismic and geodetic monitoring.
- With in-country partners involved in science advice, monitoring, aviation, national and regional administration, and civil protection, ensure our research responds to the needs of all sectors, and make recommendations for the future.
- Research outputs and methodologies supporting effective decision-making under conditions of uncertainty will assist with policy development to strengthen the resilience of people and assets exposed to volcanic hazards. Deliver to local stakeholders advice and a legacy of tools that are practical for use in a developing, low technology nation to determine optimum mitigation and resilience strategies, supporting Ethiopia's national response to the Hyogo Framework for Action international policy for disaster risk reduction. Enable DRMFSS to incorporate volcanic hazards into the local disaster risk profiling exercise.
International Organisations and Agencies
- Through organisations such as the GVM and IAVCEI commission, disseminate our results, share experience and practice applicable in a developing nation, and consult over the development of methodologies to underpin future global-scale analyses of volcanic risk.
- Transfer knowledge and contribute to policy through interaction with the UK Cabinet Office Civil Contingencies Secretariat and input to the National Risk Register.
Commercial Sector
- Collaborate with Rekjavik Geothermal and EEPCO to exchange data that inform geothermal exploration and production, and incorporate hazard analyses specific to rift volcanism to mitigate against potential future economic losses resulting from volcanic activity.

Activities detailed in the Pathways to Impact document will improve monitoring for early warning, facilitate science into policy supporting planning to build resilience, contribute to global data sets and volcanic risk modelling, increase the resilience of industry to support economic development, and facilitate better communities.

Publications

10 25 50

 
Description The Main Ethiopian Rift (MER, ~7-9°N) is the type example of a magma-assisted continental rift. The rift axis is populated with regularly spaced silicic caldera complexes and central stratovolcanoes, interspersed with large fields of small mafic scoria cones. The recent (latest Pleistocene to Holocene) history of volcanism in the MER is poorly known, and no eruptions have occurred in the living memory of the local population. Assessment of contemporary volcanic hazards and associated risk is primarily based on the study of the most recent eruptive products, typically those emplaced within the last 10-20 ky. We integrate new and published field observations and geochemical data on tephra deposits from the main Late Quaternary volcanic centres in the central MER to assess contemporary volcanic hazards.

Most central volcanoes in the MER host large mid-Pleistocene calderas, with typical diameters of 5-15 km, and associated ignimbrites of trachyte and peralkaline rhyolite composition. In contrast, post-caldera activity at most centres comprises eruptions of peralkaline rhyolitic magmas as obsidian flows, domes and pumice cones. The frequency and magnitude of events varies between individual volcanoes. Some volcanoes have predominantly erupted obsidian lava flows in their most recent post-caldera stage (Fentale), whereas other have had up to 3 moderate-scale (VEI 3-4) explosive eruptions per millennium (Aluto). At some volcanoes we find evidence for multiple large explosive eruptions (Corbetti, Bora-Baricha, Boset-Bericha) which have deposited several centimetres to metres of pumice and ash in currently densely populated regions. This new overview has important implications when assessing the present-day volcanic hazard in this rapidly developing region.
Exploitation Route Update hazard maps and assessments of Ethiopian volcanism
Sectors Energy,Environment

 
Description We contributed our expertise to hazard elicitations run by the BGS for the World Bank (2015), and for the BGS Earth Hazards and Observatories Programme (OPEN FILE REPORT OR/18/061 2018, and 2020). Building on our African partnerships, Fontijn, Pyle and Prof. Mariita (DEKUT Kenya) led a GCRF workshop on 'Volcanic and Geothermal Resources for Sustainable Development in the East African Rift' in Kenya in 2018. This brought together academic, government and professional geothermal scientists from 6 countries in Africa, and catalysed new collaborations, now led by Fontijn in Kenya.
First Year Of Impact 2015
Sector Education,Energy,Environment,Government, Democracy and Justice
Impact Types Economic,Policy & public services

 
Description GCRF Networking Grant
Amount £25,000 (GBP)
Organisation Academy of Medical Sciences (AMS) 
Sector Charity/Non Profit
Country United Kingdom
Start 03/2018 
End 12/2018
 
Description Addis Ababa University, AAU 
Organisation Addis Ababa University
Department School of Earth Sciences
Country Ethiopia 
Sector Academic/University 
PI Contribution Research training visit by Amdemichael Tadesse Zafu, long-term field assistant and assistant lecturer at AAU School of Earth Sciences, 31/07/16 - 27/08/16. He received training in sample preparation for whole rock geochemical analysis, XRF, GIS and MELTS. After his visit, additional trace element data were collected by ICP-MS (Dec 2016 and Jan 2017).
Collaborator Contribution The entire dataset is now with him and results are being interpreted to prepare for publication.
Impact None yet
Start Year 2016
 
Description Costing the Earth 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Interviewed as part of Lava: A Dangerous Game
Year(s) Of Engagement Activity 2015
URL http://www.bbc.co.uk/programmes/b055g73y
 
Description Dippy In-Depth event 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Speaker at Dippy In-Depth event (Ulster Museum in partnership with the NI Science Festival) Earth
Year(s) Of Engagement Activity 2018
URL https://nisciencefestival.com/event.php?e=20
 
Description Expert contributor Mars Diary 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact Expert contributor Mars Diary (A free primary STEM programme supported by the UK Space Agency)
Year(s) Of Engagement Activity 2018
URL https://www.marsdiary.org/experts/tamsin-mather/
 
Description George and the Blue Moon 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact I wrote a science essay in a children's book
Year(s) Of Engagement Activity 2016
URL https://www.penguin.co.uk/puffin/books/1097513/george-and-the-blue-moon/
 
Description Life Scientific 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact 30 min programme on Radio 4's Life Scientific broadcast at 9am and via podcast
Year(s) Of Engagement Activity 2017
URL http://www.bbc.co.uk/programmes/b08t0d3w
 
Description New Scientist Live 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact New Scientist Live science festival in London
Year(s) Of Engagement Activity 2018
URL https://live.newscientist.com/speakers/tamsin-mather
 
Description Oxford Science Blog on impacts of volcanic gases 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Wrote a blog about fieldwork
Year(s) Of Engagement Activity 2018
URL http://www.ox.ac.uk/news/science-blog/living-volcanic-gases-0
 
Description Pint of Science 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Pint of Science presentation in a pub
Year(s) Of Engagement Activity 2018
URL https://pintofscience.co.uk/event/volcanic-violence-and-magnetic-madness
 
Description School STEMFEST 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Workshop and talks for Year 10 students to encourage participation in STEM to A-level and beyond
Year(s) Of Engagement Activity 2018
 
Description The Forum 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Panel discussion The Unpredictable Planet: Understanding Volcanoes and Earthquakes on BBC World Service
Year(s) Of Engagement Activity 2016
URL http://www.bbc.co.uk/programmes/p041svq3
 
Description The Infinite Monkey Cage 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Part of a panel on The Infinite Monkey Cage with Brian Cox, Robin Ince, comedian Jo Brand and Clive Oppenheimer on BBC Radio 4.
Year(s) Of Engagement Activity 2018
URL http://www.bbc.co.uk/programmes/b09r47j1
 
Description The Royal Philosophical Society of Glasgow 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact First digital presentation in its 218 years of existence
Year(s) Of Engagement Activity 2020
 
Description University of Cardiff evening lecture series in the School of Earth and Ocean Sciences 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Evening lecture
Year(s) Of Engagement Activity 2020
 
Description Virtual MoD DST lecture series 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact Part of the defence science and technology lecture series
Year(s) Of Engagement Activity 2020
 
Description Volcanoes - an exhibition 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact I curated a public exhibition to run at Oxford's Weston Library from 10 February 2017 - 21 May 2017. This event attracted a lot of media coverage (print, radio and television), and parallel activities, ranging from workshops to public talks. During the exhibition over 50,000 people visited. Over 100 articles about the exhibition were published in the press, with a notional reach of 200 million potential readers.
Year(s) Of Engagement Activity 2017
URL http://www.bodleian.ox.ac.uk/whatson/whats-on/upcoming-events/2017/feb/volcanoes