Author Archives: John A. Stevenson

Easily plot magma compositions (TAS diagrams) in Python

I recently made a total alkali vs silica (TAS) plot to compare the magma of the Hekla 1947 eruption with the compositions of magmas from previous eruptions.  This post contains the code to draw the plot, including a module that … Continue reading

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Holuhraun fieldwork videos

When we sing Auld Lang Syne and raise a glass to 2015 on Wednesday, the eruption of Bárðarbunga volcanic system, Iceland, will have been going for four straight months. In that time, the eruption has covered over 80 km2 (1.3 … Continue reading

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Alaskan ash in Ireland: context, implications and media coverage

Long-range transport of volcanic ash was in the news last week, thanks to a recently published study by an international team of scientists, led by Britta Jensen and Sean Pyne-O’Donnell from Queen’s University in Belfast. They showed that volcanic ash … Continue reading

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Easily plot data on a Google Maps background with the QGIS OpenLayers plugin

It has never been so easy to overlay your data on a background of satellite images.  This post explains how to do it using QGIS, which is free/open-source software. This gives it the huge advantage that you can download it … Continue reading

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Fieldwork at the Holuhraun

Last week I joined the team from the Institute of Earth Sciences at the University of Iceland who are on the ground monitoring the eruption of the Holuhraun. This post is a description of the eruption and the monitoring work … Continue reading

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Bárðarbunga – three weeks of tweets

It’s been over 3 weeks since unrest began at Bárðarbunga, and nearly a fortnight since the fissure eruption began at the Holuhraun.  It’s come at a busy time, so I haven’t managed to blog as much as I would have … Continue reading

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Bárðarbunga – turning Dettifoss into Niagara Falls

While international concern about an eruption at Bárðarbunga is focussed on flight disruption, a jökulhlaup (meltwater flood) is the most destructive potential outcome of a subglacial eruption. It would travel north from the glacier along the Jökulsá á Fjöllum river, … Continue reading

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Bárðarbunga – waiting and watching

The word on the street in Reykjavík I’m in the Reykjavík this week on fieldwork. People here have been following developments at Bárðarbunga since the earthquakes began on Saturday. The word on the street is wait and see. The story … Continue reading

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(Almost) 3D view of Háifoss waterfall, Iceland

Háifoss is Iceland’s second highest waterfall, with a drop of 122 metres.  It’s name means ‘Milky elfin vomit spout’ in Icelandic.  Not really; it’s ‘High waterfall’.  People seem to enjoy the myth that Icelanders believe in elves.  It is located … Continue reading

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Volcanic life – the first microbes to colonise the Fímmvörðuháls lava

This is a guest post by Dr Laura Kelly, a Lecturer in Microbiology at Manchester Metropolitan University, UK. It describes her study into the first microbial life to colonise the Fímmvörðuháls lava flow, Eyjafjallajökull, Iceland. Prof Charles Cockell of the … Continue reading

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