Rift volcanism: past, present, future

Current understanding of volcanic hazards is largely derived from our knowledge and experience of activity in arc and intra-plate oceanic settings. Continental rift settings, where both effusive and explosive volcanism occur from fissure swarms, volcanic fields and stratovolcanoes, pose a different suite of challenges. In particular, the threat from large magnitude explosions and their associated hazards in rift settings, particularly in the East African Rift, has likely been highly underestimated (Aspinall et al., 2011). Towns and cities in this region are rapidly being developed with little or no regard for the long term risks posed.

BGS international work

BGS is part of a NERC Large Grant to research past and current volcanism and volcanic hazards in the Main Ethiopian Rift. The £3.7 million, five year long project 'RiftVolc' started in September 2014 and includes the universities of Edinburgh, Bristol, Cambridge, Leeds, Oxford and Southampton as well as Addis Ababa University and the Geological Survey of Ethiopia.

East African Rift

A BGS team are mapping the geology of the Afar desert in northern Ethiopia — reputed to be the hottest place on Earth.

Along the East African Rift (EAR), there is a great variety of volcano types, from large silicic calderas to basaltic fissure swarms, monogenetic cones to off-axis volcanic fields. There is a wide variation in the styles of past volcanic eruptions as well as the frequency and magnitude of these eruptions.

RiftVolc project

The project builds on previous NERC-funded projects including the Ethiopia Afar Geoscientific Lithospheric Experiment (EAGLE), the Afar Rift Consortium (ARC) and Airborne Research & Survey Facility (ARSF) data acquisition over Afar and Ethiopian rift volcanoes.

These projects focussed on magmatism and rifting in the EAR. RiftVolc is focussing on volcanoes and volcanic plumbing systems in three work packages (past, present and future volcanism) to address fundamental questions, including:

  1. what has driven eruptions over geological timescales?
  2. what controls the active magmatic system and volcanic unrest?
  3. what are the potential threats from future volcanic activity?

An improved understanding of the evolution of volcanic systems, gained from finding the answers to the first two questions, will provide the foundation on which new methods to assess and forecast volcanic hazards from high risk central volcanoes, active rift segments and volcanic fields will be developed to answer the final question.

BGS's role

BGS investigator Dr Charlotte Vye-Brown leads the third work package focussing on potential future volcanic activity with a team of seven BGS researchers and colleagues from the University of Edinburgh.

To establish what the potential threats are from future volcanic activity we will:

  1. develop probabilistic volcanic hazard assessment for key volcanic centres
  2. develop a methodology for regional analysis of volcanic hazards

Reference

Aspinall, W, Auker, M, Hincks, T K, Mahony, S, Nadim, F, Pooley, J, Sparks, R S J, and Syre, E.  2011.  Volcano Hazard and Exposure in Track II Countries and Risk Mitigation Measures — GFDRR Volcano Risk Study.  Bristol University Cabot Institute and NGI Norway for the World Bank: NGI Report 20100806; 309pp. 25.82 MB pdf

Contact

Please contact Dr Charlotte Vye-Brown if you would like to find out more about the project.