Dr. Kate Taylor Smith

Eyjafjallajökull tephra fieldwork, July 2011

2011-07-30T09:00:00.000+01:00

What a great trip. We got lots of samples that we wanted and were blessed with the weather. The Landrover didn´t break down, we saw old friends and old haunts and explored some beautiful places that I had never seen before.

Sampling Layer H tephra from Eyjafjallajökull, deposited around 1500 years ago

We should now have enough data points of thickness and samples for grain size analyses and deposit density to make significant progress with plans.

Eyjafjallajökull 2010 and Grímsvötn 2011 tephra being blown around

Some things that really struck me while we were away are a) that exponential thinning of tephra layers is certainly very close to being how things are (wow, it is hard to find where the layer goes from a trace to zero!), b) Þórsmörk is stunning especially if you cross a few dodgy looking paths and head away from the tourists, c) tephra blows around a lot after it is deposited so how can we assume geological records are good representations of the actual tephra at time of deposition? and d) Fieldwork is great and even better with good company (thanks Iveta).

Camping near Gígjökull: note the heather has coped least well with the recent ash falls

Katla in the distance under the ice cap Mýrdalsjökull. This is the Markarfljót, route of many prehistoric jökulhlaups.

Hekla 2000

2011-07-19T09:00:00.004+01:00

From Iceland to Geneva to finish off grain size analyses of Hekla 2000 tephra...

This Hekla 2000 project has been a really fun learning experience for me, going from using tephras primarily to correlate and date other deposits to specifically looking at the tephra itself. It is amazing what you can find out about a past eruption from some bags of tephra.

Samples of Hekla 2000 tephra were collected shortly after the eruption by Guðrún Larsen at the University of Iceland and other scientisits and members of the public in Iceland. It is quite unusual to have such fresh material to look at and this means that we can look at the tephra itself, hopefully reducing complications of years of reworking, compaction and contamination.

During this project I have worked with Costanza Bonadonna at the University of Geneva who has given me a lot of training and encouragment, as well as Sebastian Biass at the University of Geneva, Guðrún Larsen, Ármann Höskuldsson and Freysteinn Sigmundsson at the University of Iceland. Initial funding came from Landsvirkjun (Icelandic energy company) and the University of Iceland postdoctoral fund.

We have:

carried out grain size analyses on 31 new samples of Hekla 2000 tephra and estimated the total grain size distribution,
carried out grain size analyses on 2 samples collected near Hekla in October 2008,
analysed the componentry of the deposit and the density of tephra clasts,
re-considered the isomass mapping of the deposit and estimated volume and mass,
investigated mass eruption rate,
produced hazard curves for selected sites in southern Iceland for a VEI3 eruption of Hekla (Seb Biass)

Looking forward to bringing this all together soon.

1500 year old Eyjafjallajökull tephra

2011-07-01T09:00:00.002+01:00

I´m off in to the field to track down the Layer H tephra (sometimes called E500) from Eyjafjallajökull. This is preliminary fieldwork for a new project trying to find out more about this prehistoric eruption of Eyjafjallajökull, in collaboration with Andrew Dugmore, Anthony Newton, Thorvaldur Thordarsson at the University of Edinburgh and Guðrún Larsen at University of Iceland.

So, after this fieldwork and a bit of lab work and analyses we should be able to:

make an isopach map
calculate deposit density and produce an isomass map
estimate deposit volume and mass
carry out grain size analyses of tephra samples
estimate total grain size distribution from the deposit
assess the size and explosivity of the eruption

We already have quite a lot of thickness data from my PhD research and Andy Dugmore´s decades of research in this area and good geochemical data so this new fieldwork and sample collection campaign will help us fill out some of the gaps in geographical coverage that we have just now and all us to make some interesting comparisons between this prehistoric eruption and the more recent eruptions of Eyjafjallajökull. Exciting stuff!!

Here´s hoping for good weather and some soils where I want to find them.

Tephra in Quaternary Science: Eyjafjallajökull 2010

2011-03-26T12:58:00.005Z

5th to 6th May, 2011

Exciting: I am co-organising a workshop for the new Quaternary Research Association research group Tephra in Quaternary Science, with Prof. Andy Dugmore and Dr. Anthony Newton at the University of Edinburgh. With keynote talks from Thor Thordarson (University of Edinburgh) and Susan Leadbetter (UK Met Office) and a workshop summary from Sue Loughlin (British Geological Survey) and several discussion sessions these should be a really interesting couple of days. Many aspects of tephra to be covered: characterisation of deposits, proximal and distal deposition patterns, dispersal and modelling of tephra transport,.. and of course the Eyjafjallajökull eruptions themselves. Funding comes from INQUA and QRA and this is great because it means there doesn't have to be any registration fee and early career researchers and postgrads can be supported in their attendance. :) Looking forward to some lively discussions, a friendly few days and learning a lot.

Edinburgh Visiting Fellow

2010-11-29T12:01:00.003Z

I am now based in Edinburgh and am a visiting fellow in Geography at the University of Edinburgh while still maintaining my affiliation with the University of Iceland. I can still be contacted at kate@raunvis.hi.is.

Hazard mapping news

2008-04-20T22:11:00.009+01:00

Freysteinn Sigmundsson, Erik Sturkell and I presented preliminary results of our hazard mapping project for Snæfellsjökull at the Natural Science Symposium (Raunvísindaþing) in Reykjavík in March. Have a look here for the abstract and here for an image of the poster. Feel free to contact me for more information or for a pdf file of the poster which should be clearer.

In May we (Freysteinn, Ármann Sigmundsson and I) begin a new project, funded by Landsvirkjun, modeling tephra fallout from Hekla. This will involve collating information of past eruptive and weather conditions during activity at Hekla and resultant tephra fall patterns and characteristics. We will combine this information in a GIS system, as we have done for volcanic phenomena at Snæfellsjökull, and carry out modeling of tephra fallout and sedimentation patterns. I am impressed with how useful it has been to use a GIS system to combine and analyse spatial as well as temporal data in these hazard mapping projects and look forward to applying process-related modeling to further tailor our hazard assessments to specific eruptions scenarios, which we intend will make them much easier to interpret and understand in the event of a future eruption.

Palaeoenvironmental reconstruction as a tool in hazard assessment: a case study at Snæfellsjökull

2008-04-20T22:00:00.004+01:00

K. T. Smith, F. Sigmundsson and E. Sturkell 2008. Palaeoenvironmental reconstruction as a tool in hazard assessment: a case study at Snæfellsjökull. Poster presented at the Natural Science Symposium, University of Iceland, Reykjavík, March 2008.

Click on this here, and then again on the small poster image, for a larger jpg image of the poster.

Abstract

Here we present the results of recent palaeoenvironmental reconstructive work carried out with the aim of assessing hazard and risk from Snæfellsjökull volcano and a discussion of both the value and limitations of this approach in assessing hazard and risk.

This research aimed to assess multiple volcanic hazards at Snællsjökull by collating past work on volcanic history and augmenting this with new data collected in this project, and presented here, on volcanic floods (jökulhlaups) / lahars and tephra fall. Geomorphological and sedimentological evidence indicates that relatively small flood or lahar events have radiated from the volcano carrying pumice, most likely at or shortly after the time of major eruptions. In addition, sedimentological investigations of tephra deposition agree with past studies that showed that the main axis of tephra fall was to the east north east. Deposition of tephra from central volcanic eruptions was also found to the south and west, as were localised tephrafalls from smaller flank craters. It is clear from this study that tephra fall thickness rapidly diminished with distance from the source vent of major eruptions with over one metre of tephra found close to the present ice margin and less than 10 cm on the lower slopes of the volcano, even along the axis of deposition. Holocene lava flows [1] are primarily found to the west and south of the main volcano and from small cones on the surrounding lowlands. This work indicates that the most hazardous and widespread volcanic phenomenon likely to come from Snæfellsjökull is tephrafall, with limited hazard from floods and lava flows. However, questions remain about events common at stratovolcanoes (e.g. Öræfajökull) such as pyroclastic flows, of which no clear palaeoenvironmental evidence has yet been found at Snæfellsjökull.

This approach of basing hazard mapping on palaeoenvironmental and geological data is used throughout the world to assess volcanic hazards and it gives a excellent generalised view of how specific volcanic phenomenon may behave based on past activity and on rules definied by physical factors such as topography (e.g. flows will flow downhill and follow drainage routes). However, the useability and fullness of the results of such a project depend very much on the degree of preservation of palaeoenvironmental evidence, as well as the extent to which available resources will allow gaps in existing knowledge to be filled.

The distribution and impact of volcanic products and processes dependents upon topography, source location and meteorological conditions as well as the nature of the eruption. Consequently, there is a need for further investigation of specific past volcanic events of which little is yet known and modelling of specific likely future scenarios to develop a scenario-specific hazard and risk assessment for multiple hazards around volcanoes, including at Snæfellsjökull.

References:
[1] H. Jóhannesson, Lava flow map, produced for Snæfellsjökull National Park (Reykjavík) (pers. comm. 2005)

Raunvísindaþing 2008 poster

2008-04-20T21:56:00.007+01:00

K. T. Smith, F. Sigmundsson nad E. Sturkell 2008. Palaeoenvironmental reconstruction as a tool in hazard assessment: a case study at Snæfellsjökull. Poster presented at the Natural Science Symposium, University of Iceland, Reykjavík, March 2008.

Click on the small poster image below for a larger jpg image. Feel free to contact me if you would like a pdf file of this poster or further information. Please use the above reference for citations.

Vegagerðin research workshop

2007-12-29T21:29:00.003Z

We presented preliminary results of my most recent project (with Freysteinn Sigmundsson) at the annual workshop on Vegagerðin-funded research in a talk entitled "Volcanogenic hazards and resultant risks to road systems and infrastructure: preliminary assessments at Snæfellsjökull". You can read the abstract here.

Volcanogenic hazards and resultant risks to road systems and infrastructure: preliminary assessments at Snæfellsjökullsearch workshop

2007-12-29T21:21:00.002Z

Published abstract. Vegagerðin 2007 research workshop, Reykjavík.
Kate Smith and Freysteinn Sigmundsson

Jarðvísindastofnun Háskolans, Askja, Sturlugata 7, 101 Reykjavík.

Snæfellsjökull is a high ice-capped volcanic cone (1446 m) rising up from sea level to a 200 m deep summit crater infilled with ice. Three major phreatic (plinian) eruptions are understood to have occurred in the Holocene, the most recent being around 1855 radiocarbon years ago. Geological mapping indicates that over 25 eruptions have occurred in the Snæfellsjökull central volcano in the last 10,000 years producing lava, tephra and jökulhlaup or lahar events. Pyroclastic flows and wave (small-scale “tsunami”) effects may be likely events in a future eruption although no evidence of these has yet been identified in the geological record. Snæfellsjökull is the central focus of a national park and therefore a major travel destination. The communities of Snæfellsbær are home year-round to 1717 people, increasing dramatically during the main summer travelling season and at weekends. As we know from Öræfajökull, the eruptions of relatively infrequently erupting stratovolcanoes can be dramatic and are worthy of assessment. Should an eruption occur here in the future, nearby communities throughout the national park, several farms, airfields, the main road and bridges may be within the most hazardous regions and the impacts of tephrafall and wave effects may be felt much farther afield.

Although excellent hazard maps exist in Iceland for frequently occurring hazards such as avalanches and extensive research has been carried out on volcanic history and volcanology, few areas of Iceland have hazard maps portraying the multiple hazards associated with volcanic terrain. It is important, of course, for true resilience to natural hazards to be prepared for future hazards with full awareness of past events and likely future events, allowing strategies for dealing with natural hazard situations to be formed with access to all possible relevant information.

New research supported by Vegagerðin over the last two years has focussed on the nature and distribution of floods/lahars and tephrafall from Snæfellsjökull. Floods/lahars have flowed in many directions from Snæfellsjökull, primarily carrying pumice clasts. These floods were relatively small in comparison with historical Katla and Grímsvötn floods due to the smaller icecap and the numerous directions of flow. Tephra distribution studies back up past studies showing that the main zone of deposition was to the east north east although evidence has now been found to show that tephrafall did also occur to the west and south of the volcano. The distribution and impact of volcanic products and processes dependents upon topography, source location and meteorological conditions as well as the nature of the eruption. There is therefore variable probability of each of these events in different areas of the district and resultant variability in risk to infrastructure including roads.

Here we compile what we know about past events at Snæfellsjökull and present preliminary considerations of how this translates into hazard and risk for the district and particularly for the road system. This project aims to produce hazard maps in a manner suitable for use by a wide variety of individuals and organisations. Such maps combined with an assessment of vulnerability can be used to determine risk and to enable risk-reduction measures to be taken if required. Emphasis is placed on hazard and risk for road systems since the road network is one of the most important means of evacuation and communication and the restoration and maintenance of other lifelines depend on the movement of people and equipment to sites impacted/damaged by volcanic events.

Latest news

2007-03-09T23:06:00.001Z

I am happy to say that I, along with Freysteinn Sigurðsson at the Institute of Earth Sciences, University of Iceland, have two grant applications funded from Vegagerðin (the Icelandic Roads Administration) and Haskólí Íslands (postdoctoral fund) to work on the project "Quantifying volcanic hazards and risk for road systems - a case study at Snæfellsjökull volcano".We are working on a methodology for multi-hazard mapping with GIS at volcanoes in Iceland and elsewhere.

Jökulhlaups and implications for landscapes of settlement

2006-10-01T12:00:00.001+01:00

K.T. Smith and A.J. Dugmore (2006)
Jökulhlaups circa Landnám: mid- to late first millennium AD floods in south

Iceland

and their implications for landscapes of settlement, South Iceland. Geografiska Annaler, 88A (2): 165-176.

A late Holocene jökulhlaup

2006-09-01T12:00:00.001+01:00

K.T. Smith and H. Haraldsson (2006) A late Holocene jökulhlaup, Markarfljót, Iceland: nature and impacts. Jökull. 55, 75-86.

Jökull is the journal of the Icelandic Glaciological Society. Please contact me if you would like an offprint of this article.

Katla hazard assessment

2005-06-01T12:00:00.001+01:00

G. Larsen, K.T. Smith, O. Knudsen, A. Newton (2005) Jökulhlaup til Vestur frá Mýrdalsjökli : Ummerki um forsöguleg hlaup niður Markarfljót. 75-98. Report on Katla floods to west of Mýrdalsjökull to Icelandic Civil Protection Agency (pdf. 1522KB)

Please note, this report is in Icelandic. Please contact me if you would like more information about this work. Almannavarnadeild have very thorough pages with information about hazard assessments at Katla both to the west and south, and have pdf files of all the chapters of the report. They also produced an excellent film (Fræðslumyndin - Katla og Kötluvá) explaining about how people should act in the event of an eruption of Katla. This film and related leaflets are available from Almannavarnadeild in both icelandic (on their website) and in english (by contacting them).