Scheme: Dorothy Hodgkin Fellowship
Organisation: University of Oxford
Dates: Apr 2005-Oct 2009
Summary: I am broadly interested in volcanic hazards and the role of volcanism in planetary scale processes throughout geological time. This year I have had particular research foci on the role of volcanism in the cycling of different chemical elements between different parts of our planet and the hazard presented by the collapse of volcanic edifices, especially at glaciated volcanoes where the hazard is increasing due to glacial retreat caused by global warming. Two specific examples are summarized below:
Pressure on the world’s resources is leading ever greater numbers of people to live in close proximity to volcanoes. However, often the very nature of volcanic edifices means that they are unstable and prone to collapse. This can mean that local populations are exposed to numerous hazards (e.g., mudflows and tsunamis). We studied a specific collapse event at Yate volcano in Chile. Although this area is not densely populated we were able to learn important and widely applicable lessons pertaining to the stability and likely failure characteristics of volcanoes situated on fault zones and with glaciated summits. This is particularly important with current evidence that global warming is leading to glacial retreat in some areas and the possibility that this could lead to a period of more regular collapse events at some volcanoes.
Halogen compounds (e.g., CFCs) can play important roles in atmospheric chemistry with far-reaching consequences (e.g., the destruction of ozone), yet their processing within our planet and release to the atmosphere by volcanism is poorly quantified. We reviewed the current literature and demonstrated the important role that material being taken down into the mantle associated with subduction plays in terms of the flux of volcanic chlorine to our atmosphere. These processes are likely less important for fluorine and the challenge remains to make adequate measurements to understand the processing of the heavier halogens, bromine and iodine.