Volcanic and magmatic studies in Ireland

From the 5th-9th of January 2016, the annual meeting of the Volcanic and Magmatic Studies Group (VMSG) took place at Trinity College in Dublin. This year, the regular three-day program of talks, poster sessions and discussions was bracketed by a one-day workshop on Laser Ablation Inductively Coupled Plasma Mass Spectrometry (sometimes lovingly called LA-ICP-MS) on Tuesday 5th, and a spectacularly efficient fieldtrip to the Giant’s Causeway on Saturday 9th. As a volcanology PhD student focusing on geochemistry and petrology, everything about this program sounded intriguing to me, and I naturally signed up for both the workshop and the fieldtrip.

 

During the LA-ICP-MS workshop, we got introduced to the concept and technical aspects of spatially resolving ICP-MS data: by connecting a laser ablation system, which allows probing samples systematically in 2D (and even 3D), with an ICP-MS, it is possible to create 2D elemental maps of crystals or other sample surfaces. In addition, we dived into data reduction and imaging routines using dedicated software (the Iolite implementation in Igor Pro), playing with clinopyroxene data from Etna volcano. A fascinating and intense workshop day, and a great practical introduction to the laser ablation world, which will certainly proof useful for my research in the future.

This brings me back to my work: For my PhD, I am looking into the geochemistry and petrology of Popocatépetl volcano, Mexico (Popo). Like many arc volcanoes, Popo exhibits both effusive and mildly to highly explosive eruptions, and is active since 1994. The vast majority of studies on Popo have only addressed its explosive episodes, whereas lava streams have been largely neglected despite their obvious significance to the whole system. With my PhD, I am examining whether we can get a petrological handle on what drives the different types of eruptions: Are the source rocks different? Can we pinpoint fundamental differences in the evolution of the magmas? Or are timescales, frequencies and magnitudes of shallow-level pre-eruptive processes like magma mixing the key? In my first year, in order to address these questions, I have sampled all major lava flows making up Popo’s modern cone, as well as interspersed Plinian deposits, and determined their major, trace, and Sr-Nd isotope compositions. At the VMSG conference, I presented first petrogenetic results in a poster.

 

The conference makes a strong point in supporting early-stage researchers, and so the majority of the attendees were fellow PhD students or Postdocs, intermingled with some volcanology heavyweights. This setup helped create a very relaxed, yet productive atmosphere, with a wide range of great talks, and I had many fruitful discussions about both my work and the work of others.

A special highlight for our working group was the reception of Popocatépetl 3D models at the conference, which were produced by Ian Saginor from Keystone College, USA, and which might soon be used as illustrative models at the Natural History Museum in London, and as a hands-on visualisation of volcanic hazards in schools in communities close to Popo.

 

This way, the conference flew by, and before we knew it, it was Saturday – time to visit the Giant’s Causeway! The field trip had been meticulously planned, and necessarily so, since it is a solid three hour drive from Dublin and most people were flying out the same night. On the way to Bushmills, an expert from the Geological Society of Northern Ireland schooled us about the most important geological features we were passing by, enhanced by drive-by outcropping and prepared rock samples. At the Giant’s Causeway, we then had two hours to marvel at the basalt columns that are a product of the opening of the North Atlantic. The stormy weather made it easy to imagine how dramatic these times must have been. Shortly after, we had to wave goodbye to the sleeping giant, as we needed to make our way to the airport in Dublin.

 

This intense trip marked the end of what was a great week in Dublin. I want to deeply thank the EAG for their financial support, which made it possible for me to attend the conference. The week was an enriching experience for me, and a success for both the local organisation committee and the whole volcanological community.

About the author

Martin Mangler is a second-year postgraduate research student at Imperial College London / Natural History Museum London. His research aims to improve our understanding of the transition between effusive and explosive activity at arc volcanoes. This chiefly involves the geochemical characterisation of magmatic evolution and pre-eruptive processes and timescales for both effusive and explosive eruptions at Popocatépetl volcano, Mexico.