Return to the list of forthcoming seminars.
- # Wednesday 28th May 2025, 1.00pm – Dr Benjamin Devenish (Met Office)
- Modelling the dispersion of volcanic ash in the atmosphere
- Venue: Small Lecture Theatre (SLT), Department of Geography
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Abstract not available
- # Monday 12th May 2025, 1.00pm – Professor Claire Horwell (Durham University)
- The curious incident of the cristobalite in the Mount St Helens dome
- Venue: Small Lecture Theatre (SLT), Department of Geography
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Abstract not available
- # Monday 3rd March 2025, 1.00pm – Professor Matthew Watson (University of Bristol)
- Volcanoes, Rhinoceros and Cabbage
- Venue: Tilley Lecture Theatre, Department of Earth Sciences, Downing Street
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Abstract not available
- # Monday 11th November 2024, 1.00pm – Zoltán Taracsák (University of Cambridge)
- Tracking the behaviour of sulfur in oxidised magmas using sulfur isotopes
- Venue: Harker 1, Department of Earth Sciences, Downing Street
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Sulfur emissions from volcanoes influence Earth’s climate, have profound effects on the local environment and human health during volcanic eruptions, and provide a tool to monitor volcanic activity from space. How much sulfur is released during volcanic eruptions is a complex interplay of magma storage pressure, temperature, melt sulfur content, and melt redox state. Sulfur isotope fractionation during sulfur degassing and sulfide saturation provides information on the fate of sulfur in magmatic systems. Sulfur isotopes ratios measured in melt inclusions and glasses in oxidised magmas from ocean islands and arc magmas can help to constrain sulfur speciation in the gas and melt during melt evolution, and how changes in redox can influence where sulfur ends up in magmatic systems.
- # Monday 28th October 2024, 1.00pm – Carrie Soderman (University of Cambridge)
- The formation of co-genetic silica-undersaturated and silica-oversaturated igneous rocks: pressure, fractional crystallisation and crustal assimilation
- Venue: Harker 1, Department of Earth Sciences, Downing Street
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Alkaline-silicate igneous complexes can host significant resources of critical metals and contain a diversity of co-genetic rock types from silica-oversaturated (quartz normative) to silica-undersaturated (feldspathoid normative) compositions. The origin of these coexisting rocks is an ongoing petrological problem, due to the separation of the two regimes by thermal divides. Here we apply new thermodynamic models to investigate the co-genetic formation of these rock types using two case studies: 1) the Blatchford Lake Igneous Complex (Canada), which also hosts a world-class REE deposit associated with the silica-undersaturated units; and 2) the ‘giant dyke’ complexes in south Greenland, which our group visited this summer. We quantify the effects of fractionation, crystallisation pressure and crustal assimilation to identify key conditions under which evolved alkaline melts, which are optimal for critical metal mineralisation, may be generated.
- # Monday 14th October 2024, 1.00pm – Max Van Wyk De Vries (University of Cambridge)
- Exploring changes in exposure to glaciovolcanic hazard
- Venue: Harker 1, Department of Earth Sciences, Downing Street
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Abstract not available
- # Monday 13th May 2024, 1.00pm – Lara Mani (University of Cambridge)
- Building global resilience to volcanic eruptions
- Venue: Harker 1, Department of Earth Sciences, Downing Street
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Abstract not available
- # Wednesday 8th May 2024, 5.00pm – Blaise Mafuko Myandwi (University of Goma, DRC) and Amy Donovan (University of Cambridge)
- How can social sciences be used to explore how communities think and feel about volcanic risk and to better inform disaster risk management?
- Venue: Large Lecture Theatre, Department of Geography, Downing Site
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Abstract not available
- # Thursday 24th November 2022, 1.00pm – Dr Katrin Kleemann, German Maritime Museum – Leibniz Institute for Maritime History
- A Peculiar Haze, a Sulphuric Smell, and Bloodred Sunsets: The Effects of the 1783-1784 Laki Eruption on Europe
- Venue: Department of Geography, Small Lecture Theatre
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In mid-June 1783, a peculiar haze descended upon Europe. It quickly became apparent that this was no ordinary fog: It was dry rather than wet, lasted for months, and turned the sun and moon bloodred. Day by day, the haze grew increasingly dense. By the last week of June, the concentrations of its pollutant properties seemingly reached their peak: Contemporaries in parts of England, the Low Countries, and the German Territories reportedly tasted sulphur in the fog with every drawn breath. There were complaints of sore eyes and throats, breathing difficulties, and asthmatic attacks. Then, seemingly overnight, an apparent frost swept through towns, villages, and farms, destroying the vegetation in its path.
These events inspired many to speculate about their cause. Unbeknown to mainland Europeans at the time, a 27-kilometer-long fissure volcano had sprung to life in the remote Icelandic highlands. The Laki fissure produced the largest lava volume of any volcanic eruption in the last millennium. In Iceland, volcanic ejecta poisoned the fields, meadows, and ponds, which caused malnutrition, hunger, and disease in the human population. The jet stream then carried the ejecta to Europe, where it was a catalyst for many a fierce debate. In the spirit of the Enlightenment, naturalists used reason and experimentation in an attempt to lift the fog of ignorance.
News about this volcanic eruption only reached Europe after the fog had vanished. As a result, the real origin of this corrosive fog remained a mystery for over a century.
- # Thursday 17th June 2021, 1.00pm – Kim Huppert – GFZ Postdam
- Storms, surf, & swells: Bedrock breakdown and the geodynamic demise of volcanic ocean islands
- Venue: Zoom webinar – link to follow
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With homogeneous bedrock, dramatic climate gradients, and remnant surfaces that constrain their age, initial topography, and vertical motions relative to sea level, volcanic ocean islands provide an exceptional natural experiment in landscape evolution. Analyses traversing gradients in island climate and bedrock age have the potential to advance our understanding of climatic and tectonic influences on landscape evolution in a diverse range of continental settings. Yet, as net subsiding and boundary-dominated landmasses, islands are in some ways dissimilar to most continental landscapes, and the mechanisms of island vertical motion remain largely enigmatic. Island uplift and subsidence can provide important observational constraints on the rheology and dynamics of the Earth’s interior, in addition to setting the boundary conditions for the topographic, climatic, and biogeographic evolution of island landscapes. In this talk, I exploit steep climate gradients in the Hawaiian Islands to quantify controls on fluvial and coastal erosion, and I assess the contribution of lithosphere and mantle processes to surface deformation at ocean hotspots. Through physically-based modeling, analysis of topo-bathymetric and geochronologic data, and field measurements, I examine (1) the control of rainfall variability on long-term rates of bedrock river incision on the Hawaiian Island of Kaua’i, (2) the influence of wave power on bedrock coastal erosion in the Hawaiian Islands, and (3) the mechanisms that cause volcanic ocean islands to drown below sea level to form atolls and guyots. These analyses provide empirical support for hypothesized feedbacks between climate, tectonics, and topography, linking the evolution of the solid earth, hydrosphere, and biosphere.
- # Thursday 27th May 2021, 1.00pm – Simon Matthews – University of Iceland
- Crystallisation temperatures as a proxy for mantle temperature; and the 2021 eruption in Reykjanes
- Venue: Zoom webinar – link to follow
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Abstract not available
- # Thursday 18th March 2021, 1.00pm – Aleeza Wilkins and Alice Pennaz (USGS)
- 2018 Eruption of Hawaii’s Kilauea Volcano – Use of Social Media and the U.S. Department of Interior Strategic Sciences Group
- Venue: Zoom webinar – link to follow
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The 2018 Kilauea eruption, which began on May 3 and lasted 107 days, was one of the longest eruptions in recent history in the lower Puna district of Hawaii. Over 700 homes were destroyed, and there was additional damage to the USGS Hawaiian Volcanoes Observatory as well as to critical infrastructure within the Hawaii Volcanoes National Park. Many federal, state, and local agencies and organizations supported response to this historic event. In this seminar, the speakers will describe how the USGS used social media to deliver nearly 24/7 volcano hazards information and build trust during the crisis. The speakers will then describe how the unique approach of DOI’s Strategic Sciences Group (SSG) provided insights to help identify potential social, environmental, and economic consequences of the eruption.
- # Thursday 4th March 2021, 1.00pm – Dr Audrey Michaud-Dubuy, Institut de Physique du Globe de Paris
- Refined eruptive history of Mount Pelée volcano and implications for tephra fallout hazard in Martinique
- Venue: Zoom webinar – link to follow
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Mount Pelée volcano (Martinique) is one of the most active volcanoes in the Lesser Antilles arc with at least fifteen magmatic events in the last 5,000 years, including the deadliest eruption of the twentieth century in 1902. Our knowledge of the eruptions older than 5 ka is however very limited, thus reducing our capacity to predict the dynamics of future eruptions at Mount Pelée.
Two new extensive field studies performed in 2017 and 2019 in Martinique combined with carbon-dating measurements allow us identifying six new eruptions in the past 24 ka cal BP, including four Plinian and two Pelean eruptions. We reconstruct the dynamical evolution of the newly discovered Plinian eruptions of Bellefontaine (13.5 ka cal BP), Carbet (14 ka cal BP) and Etoile (21.5 ka cal BP) whose great interest stems from their unusual southward dispersal axis encompassing areas that are considered to be safe in current hazard maps. Using the 2-D ash dispersion HAZMAP model, we identify peculiar atmospheric circulations associated to a modification of the subtropical jet-stream path producing northerly winds over Martinique and thus spreading ash towards the most populated areas of the island.
This integrated approach, combining field studies and model predictions, allows us to build new volcanic hazard maps for tephra fallout in Martinique. Our method is based on 16 eruptive scenarios, consistent with the data retrieved from our stratigraphical records. Each scenario considers a different pair of deposit mass and mass discharge rate, and is given a probability of occurrence calculated from the complete eruptive history of the volcano. We use the ERA-5 database to consider the daily variability of winds. These new probability maps, as well as the predicted range of damages that could be expected at key infrastructures in Martinique, will be useful to revisit the emergency procedures as the volcanological observatory (OVSM) recently raised Mount Pelée volcano on alert level 2.
- # Thursday 18th February 2021, 1.00pm – Dr Esti Handini, Universitas Gadjah Mada
- Looking Through the Sunda Arc: An Overview of Java’s Magmatism
- Venue: Zoom webinar – link to follow
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The Sunda arc is a simple-looking island arc at the western tip of Pacific Ring of Fire, extending from the Andaman islands in the North and Sumatra in the West to the small volcanic islands in the north of Savu Sea in the East. The current active arc is built on top of composite crustal blocks, and has been active since Miocene. This more recent style of activity occurred after the Cretaceous subduction period ceased, and arc activity shifted towards the north. Today, the Sunda Arc is one of the most active volcanic arcs in the world, with 95 Quaternary volcanic centers.
The groundwork on Sunda arc magma geochemistry was laid in the 1970s (as early as 1973), and has now reached a new peak of data accumulation and complexity. This allows us to look through a large-scale systematics of arc geochemistry. Understanding this geochemical framework should provide an opportunity to understand the interplay between the three main subduction zone components (i.e., mantle source, subducting slab, and the overriding crust) and their role in the generation of magmas along Sunda arc.
This talk will provide (1) an introduction to the general geochemical systematics along Sunda arc, followed by (2) a closer look into the across-arc chemical systematics in Central Java. In the first part I will briefly show you the geochemical variation of volcanics from along the arc to show the variable association with the underlying crustal blocks. In the second part I will highlight my recent work, which seeks to untangle the subduction contribution across Merapi-Muria volcanic line in Central Java, where the slab-mantle wedge interface goes deeper than the rest of the arc segments, using trace elements and radiogenic isotopes - # Thursday 19th November 2020, 1.00pm – Jacob Richardson, NASA/GSFC
- Exploring volcanoes in Central Iceland as Analogs for Planetary Environments
- Venue: Zoom webinar – link to follow
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Abstract not available
- # Thursday 5th November 2020, 1.00pm – Alia Juman, University of the West Indies, St. Augustine
- A Caribbean Vacay: Sun, Sand, Sea and Volcanoes?! An introduction into volcanic outreach in the Eastern Caribbean
- Venue: Zoom webinar – link to follow
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Abstract not available
- # Thursday 22nd October 2020, 1.00pm – Joshua Jones (Virginia Tech)
- Modeling volcano-tectonic interactions in a youthful continental rift: the East African Rift System
- Venue: Zoom webinar – link to follow
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Abstract not available
- # Thursday 8th October 2020, 1.00pm – Dr Julie Morin, Department of Geography
- Integrating social and institutional vulnerabilities into volcanic risk scenarios: A case study at Nevado Cayambe, Ecuador
- Venue: Zoom webinar – link to follow
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Eight hundred million people live near active volcanoes worldwide, however many of them have never experienced volcanic eruptions or their associated hazards. While the volcanologist community provides essential understanding about volcanic systems, geographers and other social scientists share an equally fundamental role in assessing dimensions of vulnerability and risk and aiding preparedness efforts and managing volcanic crises.
Our current case study focuses on Cayambe Volcano in Northern Ecuador, which began to show signs of unrest in 2016. It is covered with a 22 km2 glacier that could trigger deadly mudflows in the city of Cayambe in a future eruption. However, little was done to prepare the population. As geographers facing the evidence of this preparedness “void”, we desire to build a pilot rapid assessment framework, based on data collected at Cayambe, which can be used to minimize the impact of hazard events. The framework includes for instance vulnerability assessments, risk perception, and evacuation modelling. It beneficiates from the inputs of colleagues from other disciplines working in volcanic environments, and from the close collaboration of the local communities and Civil Protection authorities. We aim to provide a set of preliminary guidelines for building a “social sciences framework” and conducting a rapid assessment to better address complex cases of volcanic unrest at other understudied, potentially active volcanoes.
- # Thursday 18th June 2020, 1.00pm – Emma Horn, University of Southampton
- Snapshot of a magmatic system immediately prior to an explosive eruption: Tenerife 289 ka
- Venue: Webinar (via Zoom online)- link to follow
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Abstract not available
- # Thursday 11th June 2020, 1.00pm – Callum Reekie, Earth Sciences Department, University of Cambridge
- Exploring controls on the distribution of sulfur-loving elements in Icelandic magmas
- Venue: Webinar (via Zoom online)- link to follow
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Chalcophile (sulfur-loving) and siderophile (iron-loving) elements (e.g., Cu, Ag, Pt and Au; collectively called CSE) are of significant economic importance. In basaltic melts, the abundance and distribution of CSE is chiefly controlled by sulfide minerals, both during partial melting and crustal differentiation processes. Typically, melts depleted in CSE are considered to have become sulfide-saturated during crustal differentiation. However, recent work has shown that CSE abundances and ratios correlate with lithophile element proxies which are sensitive to mantle fertilisation and melting processes. In this talk I will discuss our results from Icelandic basalts. Importantly, Icelandic basalts have been shown to be derived from a chemically and lithologically heterogeneous mantle source, and could therefore be key to unravelling the different controls on CSE variability in basaltic melts.
- # Thursday 4th June 2020, 1.00pm – Dr Emma Liu, University College London
- Volcanic activity along the enigmatic South Sandwich arc
- Venue: Webinar (via Zoom online)- link to follow
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Abstract not available
- # Thursday 28th May 2020, 1.00pm – Lis Gallant (University of Cambridge)
- Assessing hazards in distributed volcanic fields
- Venue: Webinar (via Zoom online)- link to follow
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Abstract not available
- # Thursday 21st May 2020, 9.00am – Rachael Baxter, Earth Sciences Department, University of Cambridge
- Initiation of a composite volcano: The complex beginnings of the long-lived Dunedin Volcano, New Zealand
- Venue: Webinar (via Zoom online)- link to follow
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Abstract not available
- # Thursday 14th May 2020, 1.00pm – Dr Elena Maters (University of Cambridge, Department of Chemistry)
- Experimental insights on volcanic ash as a reactive agent in the environment
- Venue: Webinar (via Zoom online)- link to follow
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Abstract not available
- # Wednesday 19th February 2020, 1.00pm – Lauren Davies, University of Alberta
- Implications of Holocene cryptotephra records in North America
- Venue: Department of Earth Sciences – Harker II
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Records of far-travelled volcanic ash, not visible to the naked eye but detectable in sediment records, have expanded in North America over the past 12 years. Analyses of ash transported from volcanic source regions over 1000s of km away, including Kamchatka, Alaska and central America, provide detailed data across the Holocene that can be utilised for many purposes. This seminar will touch on what records have been produced, some practical lessons learnt about undertaking this work in North America, and implications of the new datasets for other research topics, including eruptive histories, atmospheric circulation and independently assessing modern chronostratigraphies.
- # Monday 2nd December 2019, 12.30pm – Marie Edmonds
- Daly Lecture Preview
- Venue: Department of Earth Sciences – Harker II
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Abstract not available
- # Monday 2nd December 2019, 12.00pm – Cambridge University
- Tracking sulfur and its chalcophile allies at Kilauea Volcano, Hawaii: A story of sulfide saturation, sulfide resorption and magmatic degassing
- Venue: Department of Earth Sciences – Harker II
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Abstract not available
- # Wednesday 27th November 2019, 12.00pm – Kate Laxton, University College London
- Unusual techniques for an unusual volcano: monitoring at Ol Doinyo Lengai
- Venue: Department of Earth Sciences – Harker II
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Abstract not available
- # Wednesday 20th November 2019, 1.00pm – Amber Madden-Nadeau, University of Oxford
- The magmatic and eruptive evolution of the 1883 explosive, caldera-forming eruption of Krakatau, Indonesia
- Venue: Department of Earth Sciences – Harker II
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Abstract not available
- # Wednesday 13th November 2019, 12.00pm – Bridie Davies, University of East Anglia
- Unravelling the Echo Canyon deposit: Explosive-effusive transitional volcanism, Ascension Island, South Atlantic – Insights from the field and the lab
- Venue: Department of Earth Sciences – Harker II
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Abstract not available
- # Wednesday 30th October 2019, 12.00pm – Dan Spencer, University of Oxford
- How volcanism controls the interiors of lava-worlds
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Jupiter’s moon Io is the most volcanically active body in the solar system, and is part of a growing class of discovered ‘lava-worlds’. Volcanism transports vast quantities of heat from Io’s interior to the surface, a heat transfer mechanism with significant implications for interior structure. We present a model of coupled magmatism and volcanism applied to Io. Intrusive and extrusive rates control the thickness of Io’s crust, whilst continual melting and extraction from the interior, together with suppressed convection could have resulted in a strongly layered mantle. Our results are in agreement with all currently available observations of Io, and present hypotheses readily testable by future missions.
- # Wednesday 16th October 2019, 12.00pm – Speaker to be confirmed
- New PhD students introductions – Cambridge Volcanology
- Venue: Department of Earth Sciences, Tilley Lecture Theatre
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Abstract not available
- # Wednesday 8th May 2019, 12.10pm – Penny Wieser, University of Cambridge
- Tracking chalcophile elements from source to vent at Kilauea Volcano, Hawaii
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Kilauea Volcano emits globally significant quantities of S and sulfur loving (Chalcophile) elements into the atmosphere. These emissions have serious implications for respiratory health and agricultural productivity across the island. Yet, the processes controlling the concentration of these elements in erupted melts are enigmatic. Using high precision major and trace element measurements in melt inclusions and matrix glasses, we demonstrate that chalcophile element systematics at Kilauea are controlled by a number of processes, including the presence of sulfide in the mantle source, sulfide-liquid immiscibility during fractionation, sulfide resorption upon eruption, and the degassing of traditionally “refractory” chalcophile elements (e.g. Se). Our conclusions differ substantially from those of previous work, largely because in the literature, chalcophile elements have only been investigated in lava lakes (where the behaviour of S is anomalous due to syn-eruptive degassing).
- # Wednesday 1st May 2019, 12.00pm – Professor Christine Lane, Department of Geography, University of Cambridge
- Masterclass: An introduction to distal tephrochronology and cryptotephra methods
- Venue: Harker 2, Department of Earth Sciences, Downing Street
- # Wednesday 5th December 2018, 12.00pm – Thomas J. Aubry, University of British Columbia
- Will climate-volcano interactions be modulated by ongoing climate change? Perspective from explosive eruption column rise.
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Volcanic eruption plumes reaching the stratosphere result in the formation of long-lived (1-2 years) sulfate aerosols, which interact with Sun and Earth radiation and alter the radiative balance of our planet. In particular, stratospheric volcanic aerosol forcing results in a net cooling of Earth’s surface. As CO2 concentration increases due to anthropogenic emissions, changing weather and climate may affect multiple processes that govern the climatic impact of volcanic eruptions. Will we experience increased or decreased volcanic cooling on a warming Earth? This will be the central question of the seminar. I will focus in particular on how the rise of volcanic plumes and the injection of sulfur gases into the stratosphere may be affected by ongoing climate change.
First, I will discuss the ability of simple (0D, 1D) volcanic plume models to predict volcanic plume heights. Such models commonly require empirical constraints for processes such as the turbulent entrainment of atmosphere into a volcanic column, and are subject to large uncertainties. I will show how recent laboratory experiments and a newly compiled database of eruption source parameters improve constraints and evaluation of volcanic plume models. I will explore the implications of this new work for the prediction of volcanic plume heights and the production of pyroclastic flows, and discuss future steps for producing datasets that will enable a better evaluation of volcanic plume models.
Second, I will use the same volcanic plume models along with climate projections, a volcanic aerosol forcing model, and past records of volcanic sulfur emission to investigate the potential effects of climate change on volcanic plume rise. I will show that reduced volcanic sulfur injections into the stratosphere are projected with ongoing climate change. A novel feedback hypothesis emerging from this work is that volcanic cooling may be reduced on a warming Earth. I will discuss future plans to investigate this feedback in the UK Earth System Model along with feedbacks that could affect different processes governing the climatic impacts of future eruptions.
- # Wednesday 28th November 2018, 12.00pm – Ben Ellis, ETH Zurich
- Lithium, rhyolites, and the green revolution
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Lithium (Li) plays an increasingly important role in society with ever greater reliance on rechargeable batteries for a variety of uses from handheld electronic devices to electric vehicles. Seemingly, there is a relationship between the locations of economic Li deposits and silicic magmatism, however relatively little is known about the behaviour of Li in silicic magmatic systems. This talk will initially discuss how the unusual geochemical properties of Li allow it to remain mobile into the post-eruptive realm and how this mobility obscures ‘true’ magmatic signatures. Subsequently, the talk will focus on situations where Li does preserve information about magmatic and eruptive processes and speculate about what Li may be able to reveal about the magmatic-hydrothermal transition.
- # Wednesday 21st November 2018, 12.00pm – Penny Wieser, Emily Mason; University of Cambridge
- Measuring gas emissions at the 2018 Leilani Estates eruption, Kilauea
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Two graduate students Emily and Penny recount their recent field expedition to the Leilani Estates fissure eruption of Kilauea volcano, Hawai’i.
- # Wednesday 14th November 2018, 12.00pm – Craig Walton, Pip Liggins; University of Cambridge
- Phosphorous pathways in Deep Time / Atmospheric Fingerprints of Volcanism
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Two new graduate students Craig and Pip introduce themselves and their research.
- # Wednesday 7th November 2018, 12.00pm – Nick Barber, Johnny Staunton-Sykes; University of Cambridge
- tbc // Sulfur isotopes as tracers for stratospheric volcanic sulfur loading
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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New graduate student Nick Barber will present on his Masters research, GIS applications and mapping the Deccan traps, before introducing his PhD research on metals in volcanic gas emissions.
Second year PhD student Johnny Staunton-Sykes is an atmospheric chemist, and will present on one aspect of his doctoral research, whether mass independent fractionation of volcanic sulfur can be used as a tracer for stratospheric sulfur loading after explosive eruptions.
- # Wednesday 24th October 2018, 12.00pm – Evgenia Ilyinskaya, University of Leeds
- Globally Significant CO2 Emissions From Katla, a Subglacial Volcano in Iceland
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Volcanoes are a key natural source of CO2, but global estimates of volcanic CO2 flux are predominantly based on measurements from a fraction of world’s actively degassing volcanoes. We combine high‐precision airborne measurements from 2016 and 2017 with atmospheric dispersion modeling to quantify CO2 emissions from Katla, a major subglacial volcanic caldera in Iceland that last erupted 100 years ago but has been undergoing significant unrest in recent decades. Katla’s sustained CO2 flux, 12–24 kt/d, is up to an order of magnitude greater than previous estimates of total CO2 release from Iceland’s natural sources. Katla is one of the largest volcanic sources of CO2 on the planet, contributing up to 4% of global emissions from nonerupting volcanoes. Further measurements on subglacial volcanoes worldwide are urgently required to establish if Katla is exceptional, or if there is a significant previously unrecognized contribution to global CO2 emissions from natural sources.
- # Wednesday 17th October 2018, 12.00pm – Nick Blegen, University of Cambridge
- Volcanic applications for understanding the evolution of human behavior in East Africa
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Abstract not available
- # Wednesday 10th October 2018, 12.00pm – Sam Poppe, Vrije Universiteit Brussel
- An unusual patient: quantifying 3D deformation around analogue magma intrusions by using X-ray Computed Tomography
- Venue: Harker 2, Department of Earth Sciences, Downing Street
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Magma intrusions grow to their final geometries by straining the Earth’s crust internally and displacing the Earth’s surface. Interpreting that volcanic unrest is key to forecasting a volcanic eruption. While scaled laboratory models enable us to study the relationships between surface displacement and intrusion geometry, past approaches entailed limitations regarding imaging of the model interior or simplicity of the simulated rheology.
This talk presents results from combining state-of-the-art wide beam X-ray Computed Tomography (CT) and Digital Volume Correlation (DVC) to quantify in 4D the deformation induced in laboratory models by an intrusion of a magma analogue (golden syrup) in a granular Mohr-Coulomb host material (sand and plaster). The evolution of the extracted surface deformation and strain field of the entire experimental volume in 3D over time shows how contrasting geometries – cryptodomes, cup shapes, cone sheets and dikes – form in host material of different strength. Moreover, contrasting geometries induce contrasting propagation modes and strain field characteristics in the host.
Our results demonstrate how the combination of CT and DVC can greatly enhance the utility of optically non-transparent crustal rock analogues in obtaining insights into crustal deformation processes. This unprecedented inside perspective helps understanding the limitations of simple elastic rheology used in geodetic and inversion modeling of crustal deformation processes.