Sunday, February 19, 2012
Exhibit Hall A-B1 (VCC West Building)
The eruptions of Eyjafjallajökull in 2010 caused widespread travel chaos across the globe, with over 100,000 cancelled flights which affected up to 10 million passengers. While the events of 2010 are well known the recent history of the volcano is not. This paper extends the volcanic history of Eyjafjallajökull by describing the Hoftorfa tephra (volcanic ash) layer from an eruption of the central crater and two flank eruptions- late prehistoric activity along Migtungugil about 1500 years ago and the ca. 920 AD eruption of the Skerin fissure. The pursuit of improved understanding of recent volcanic activity highlights two key issues: how to approach the identification of past eruptions and what might be the relationship between long-term patterns of activity in Eyjafjallajökull and its close neighbour Katla. The Migtungugil and Skerin eruptions have been recognised using tephrochronology even though they did not produce extensive tephra deposits, because they did generate floods. Tephrochronology using layers from other volcanoes is applied to the identification, correlation and chronology of these flood deposits. Evidence is scattered, lacks clear sedimentological markers and could have completely escaped attention but for the precise correlations possible with tephra layers. There is evidence that both the Migtungugil and Skerin eruptions coincided with Katla eruptions.