Scientific Symposia

Bubbles play a pivotal role in driving, modulating, and recording volcanic and magmatic processes. They drive eruptions by providing the buoyancy that mobilizes magma from its crustal storage and propels it upwards through the volcanic plumbing system. They modulate the style, intensity, and impact of eruptions by altering the rheology of magma and lava flows, and by creating the over-pressure that causes explosive fragmentation. They record and reveal the history of magma ascent through the textures they create in eruptive products, through their capacity to fractionate, transport, and release the volatile species they contain, and as sources of geophysical signals. Bubbles have relevance, therefore, across the breadth of volcanic and magmatic studies, and act as a common point of reference around which we aim to stimulate interdisciplinary discussion.

We invite contributions from researchers and practitioners whose work addresses any aspect of the role of bubbles in magma, including studies of bubbles themselves, and broader studies of magmatic and volcanic processes in which the behaviour of bubbles plays a role. Topic areas include, but are not limited to:

1. The physics of bubbles in magma – bubble formation, growth, resorption, deformation, interaction, coalescence, bursting, and their influence on thermal, mechanical and other physical properties of magma.
   
2. The effect of bubbles on volcanic processes – magma mobilization, ascent, convection, mingling, rheology, degassing, outgassing, permeability, fragmentation, and transport of volatiles.
   
3. The role of bubbles as informers on pre-, syn-, and post-eruptive processes – vesicle size, shape, and spatial distributions, spatial distribution of dissolved volatiles, gas geochemistry, bubbles as sources of infrasound and seismicity.
   

We anticipate contributions that adopt a wide range of field, experimental, analytical, and numerical approaches, and particularly encourage contributions that employ novel research methodologies, or that bridge across traditional disciplinary areas.

From a magma chamber to the Earth’s surface, the physical properties of ascending magmas change dramatically through bubble nucleation and growth, outgassing, groundmass crystallization, glass transition, and fragmentation. These processes are recorded by petrographic features in erupted materials, such as microstructures of bubbles and groundmass crystals, compositional zoning of phenocrysts, and volatiles in melt inclusions of phenocrysts and matrix glasses. Conversely, the physical properties of the actual multiphase magmas are affected by bubbles, volatiles, and crystals. Moreover, the totality of these processes influences the eruptive style of volcanoes and the patterns of the geophysical observations at the surface. 

Approaches employed analyses of microstructures and physical properties of erupted materials in recent studies are diverse, ranging from atomic-scale analyses of melt structures and high-resolution chemical analyses to geodetic observation coupled with the excess-pressure calculation of the magma feeding system. The aim of this session, therefore, is to bring together recent advances in different fields and discuss what we have achieved on the eruption processes so far, and to foresee the future direction. We welcome contributions from a wide range of scientific disciplines, including petrographic analyses of natural samples, laboratory simulation experiments of eruptive processes, interpretations of eruption processes on the basis of geophysical observations, and numerical modeling of magma ascent processes.

Our understanding of the eruption dynamics of silicic magmas has evolved over the last ten years, largely due to observations made during and after the eruptions of Chaitén (2008-2009), Cordón Caulle (2011-2013), and Havre (2012). Pre-existing models of silicic volcanism have been unable to reconcile direct observations made during these eruptions, such as previously unseen “hybrid” activity where the eruption style was simultaneously explosive and effusive, and new styles of silicic lava flow emplacement. However, questions remain regarding how applicable new observations are to future and historic eruptions. Evidence of conditions during volcanic eruptions are preserved in the products of volcanic eruptions. By integrating field and laboratory measurements of pyroclasts and lava, a better understanding of conduit dynamics and the relationship between explosive and effusive styles can be gained. The goal of this session is to share the current understanding of the eruption of silicic magmas through field and laboratory measurements leading to a better understanding of explosive and effusive eruption dynamics of silicic magmas. 

Volcanic systems involve a range of dynamic processes that trigger eruption and govern magma ascent. Eruption can be triggered by several mechanisms, such as rapid intrusion of fresh magma and mixing in the magma storage zone. Once the eruption is triggered, several interdependent processes take place during magma ascent from a crustal storage region to the surface, shaping the nature of eruptions and associated phenomena. These processes include crystallisation, degassing, fragmentation and possible fluid migration in and out of the plumbing system. Understanding and quantifying the triggering mechanisms and processes that occur during magma ascent is of critical importance for improving prediction of eruption style, evolution, and duration. However, despite advances in the characterisation of individual magmatic processes, our understanding of their two-way interactions and the consequent control on volcanic activity remains limited. This session invites contributions that address this topic, preferably through integration of at least two approaches, such as experimental, numerical, observational, and/or analytical/petrological. 

Growing evidence suggests that mush systems can build up over protracted periods and yet catastrophically switch to a state of unrest and eruption on near-instantaneous timescales, posing a major challenge for volcano monitoring efforts. Understanding the birth, growth and potential mobilisation of mush systems is hence of major interest in volcanology, and requires a comprehensive approach to the study of magma transport, storage and differentiation through the crust. Crucially, the rates, depths and complexities inherent to magmatic plumbing systems have a major impact on the behaviour, duration and intensity of ensuing volcanic eruptions. 

We invite a wide range of contributions including field, petrographic, geochemical, experimental, numerical and/or geophysical approaches to constrain the spatio-temporal evolution of mush systems and the key processes that lead to eruption. We encourage combinations of conventional methodologies with innovative techniques to interrogate petrological and geochemical records and their links to monitoring data.   

Volcaniclastic aprons or ring plains develop around volcanic centres of all sizes and types by deposition of syn- and post-eruptive volcaniclastic material, minor primary products and sedimentary deposits. These successions represent valuable archives that hold a detailed record of volcanic and other landscape-shaping events and often provide the only means to reconstruct the long-term volcanic history of a region. The ability to accurately interpret the origin, transport and emplacement processes of the observed deposits is thus crucial to better understand the nature, magnitude and frequency of future volcanic hazards, including the potential for catastrophic edifice failure. Variations within the comprised lithofacies can also be linked to the key influences on ring-plain accumulation and landscape evolution, including the respective controls of volcanic activity, climate and geomorphic setting. While ancient to modern volcaniclastic records indicate that mass-wasting processes pose significant, often enduring secondary hazards that are common in volcanic landscapes, non-volcanic environments can also experience smaller-scale but potentially increasingly more frequent sediment remobilisation and landscape adjustment events in response to e.g. large wildfires, droughts and landslides. 

This session provides a forum for discussing long-term volcanic behaviour recorded in volcaniclastic sequences and recent advances in quantifying initiation thresholds, frequency and magnitude of the full spectrum of secondary volcaniclastic processes. We invite contributions that address all aspects of volcaniclastic sedimentation, from field data collection aimed at interpreting transport and emplacement processes of volcanic mass flows and reconstructing volcanic histories to application of statistical and computer models focused on quantifying secondary volcanic hazards. 

This session explores and celebrates the rewards, successes, and challenges of working with stakeholders and non-academic partners towards scientific outcomes are useful, useable, and used. We solicit contributions that (1) highlight examples of research informed by stakeholder engagement through to co-created research, (2) provide tips and strategies for effective and productive collaboration and knowledge implementation, (3) share approaches for building trust and nurturing long-lasting partnerships, and/or (4) reflections on ensuring science directly benefits society. We welcome contributions from scientists, stakeholders, and observers. 

Effective communication of science and risk and science information pre-, during, and post- a volcanic crisis is vital for volcanic risk management planning, mitigation, response, recovery and resilience building activities. This scientific information can range from technical risk assessments, to impact projections, simulations of physical processes, forecasts and warnings, economic projections, and outcomes of recovery and adaption decision-making tools. A range of agencies and individuals are involved in this communication, from public individuals through to risk management agencies and policy makers, as well as other scientists and technical agencies. The value of this information is vital to inform decision-making at each of these levels, and should ideally directly address the needs of the decision maker. Such a goal is desired through participatory and other ways to developing science (including citizen science) that adopt a decision-relevant and demand- led approach to scientific research and communication with, rather than to, individuals and agencies. 

In this session, we are seeking contributions that outline case study examples, primary research, or systematic reviews, that identify lessons that can improve the effective communication of volcanic risk and science, forecasts and warnings, and the range of uncertainties (both epistemic and stochastic). We are particularly interested in lessons drawn from a multi-hazard perspective, participatory or citizen science approaches, and other forms of knowledge transfer. Finally, empirical studies that explore and evaluate effective communication products are strongly welcomed. 

While communication is rarely straightforward, some topics are more challenging than others. In this session, we seek to learn from our community’s broad expertise in communicating topics that are particularly hard to convey, either because of public knowledge, risk perception, messaging fatigue, or our own scientific uncertainty.

Topics may include, but are not limited to:

• How to communicate about low-probability, high-impact hazards, such as large-scale caldera eruptions;
  
• How to communicate about high-impact, low-visibility hazards, such as harmful gas emissions and prolonged ashfall;
  
• How to communicate uncertainty in crisis or calm, to strengthen trust and build credibility;
  
• How to understand and communicate relevant social science, such as risk perception and health impacts, within the volcanology community; and
  
• How to address misinformation and mistakes, whether ours or someone else’s.
  

We can learn from both successes and failures. We hope this session will bring the volcanology community together to share how communication of difficult topics can serve at-risk communities, the interested public, researchers, agencies, and outreach efforts. 

Volcano observatories (VO) provide critical information and interpretation about the status and potential activity of the volcanoes within their area of responsibility that inform local and national decision making to help reduce disaster risk and manage crises. For aviation and transboundary hazards, reporting may be directed more widely. In addition, there is an ever-increasing international audience of stakeholders including national governments, international humanitarian organizations, the private sector, researchers of various disciplines, the media, and an interested and more involved global public. These stakeholders and others, all use volcanic activity information provided by VOs. International stakeholders use the information and data in various ways, including to provide situational awareness, make decisions, interpret satellite data, and populate large open-source databases of volcanism. In some cases (e.g. earth observation, VAACs, the public) valuable observations and additional data can be collected and sent back to observatories during a crisis. The aim of this session is to share perspectives, approaches, and lessons learned in communicating information on volcanic activity to a variety of audiences beyond the national scale, highlighting success stories and opportunities. To foster knowledge exchange and exploration of the theme, the talks will be followed by a discussion at the end of the session.  

Volcanic unrest, volcanic eruptions and their aftermath are associated with multiple primary and secondary hazards, which pose short- to long-term threats to people and property. Experience has shown that success in the management of volcanic risks strongly correlates with the degree to which proactive policies of risk reduction are in place before an eruption begins. Such policies should ideally be developed based on comprehensive analysis of the volcanic risk encompassing the full spectrum of volcanic primary hazards (e.g. pyroclastic density currents, lava flows, tephra accumulation and dispersal, gas emissions) and interacting hazards (e.g. lahars triggered by intense rainfall) as well as associated vulnerabilities (e.g. physical, systemic, social, economic, institutional). Risk associated with volcanic eruptions has been recognized as complex and dynamic for many decades, yet still no comprehensive methods for vulnerability and risk analysis are widely accepted. Currently several initiatives are attempting to develop models and methodologies to assess volcanic risk. We welcome contributions presenting strategies for the assessment of exposure, vulnerability and risk; discussing ways of identifying and characterizing elements at risk; combining hazard, exposure and vulnerability; presenting vulnerability and risk assessment in a multi-hazard setting; describing how to benefit from local knowledge through participatory risk assessment; and showing how dynamic vulnerability and risk assessments should be carried out to implement useful mitigation measures. 

Volcanic eruptions pose a considerable threat to the wellbeing and livelihoods of communities living near active volcanoes. Notably, a range of human health conditions may arise from exposure to eruptive and passive degassing, ashfall, and resuspension of deposited material, particularly since ash and gases can be transported over great distances. Human physical health can also be affected in various ways, including fatalities and injuries from pyroclastic flows/surges, lava flows and ballistic projectiles, whereas exposure to fine-grained ash and gases can exacerbate or potentially induce respiratory diseases and symptoms, and cause eye and skin irritation. Other, more indirect, effects include contamination of water supplies and loss of crops, and psychological distress related to the eruption crisis.

New Zealand has a number of active volcanoes and volcanic fields, which have the potential for eruption in the foreseeable future. Consideration of such hazards, and those from geothermal fields such as the Rotorua Geothermal Field, are of importance because of their potential impact on population health and the overall economy of New Zealand. Co-ordinated, multi-disciplinary efforts are needed to assess and successfully prepare for health hazards associated with volcanic phenomena, and to provide timely advice to anxious populations and emergency managers during volcanic crises. 

In this session, we welcome submission of abstracts from a broad range of disciplines relating to human health in volcanic areas, including: i) community exposure and protection, ii) health hazard and impact assessment (mineralogical, toxicological, clinical and epidemiological studies), iii) air and water quality monitoring and forecasting, iv) risk assessment and hazard management, including modelling studies predicting health impacts from future eruptions, v) community preparedness and response to volcanic eruptions. 

This session is sponsored by the International Volcanic Health Hazard Network, an IAVCEI Commission (www.ivhhn.org). 

When faced with questions about future eruptive activity at a particular volcano, volcanologists often seek out analogous volcanoes or similar patterns of past unrest for comparison and inference. Analog sets of volcanoes or eruptions can be especially helpful when dealing with data poor volcanoes. However, identifying the most appropriate sets of potential analogs remains a significant challenge. There is no ‘one size fits all’ approach for identifying analogs because: (1) the physical-chemical processes that justify the volcano analogy can have very varied scales in time and space (e.g. magma generation/differentiation versus fragmentation); (2) different types of analogs may be required depending on the target (e.g. volcano, unrest episode, or eruption) and purpose of the analog analysis. For example, questions about the potential size of future eruptions may require analog sets of volcanoes with similar morphologies, chemistries, and eruptive behavior; whereas, questions about lahar hazard might require analog sets of volcanoes with similar climates, snow and ice cover, and slope topography. Finally, the data sources used to identify the analog sets may also be diverse: global databases of volcanoes, unrest, and eruptions; local monitoring data; expert knowledge; and other datasets. This session seeks contributions that explore ways in which to identify analog sets of volcanoes and their patterns of unrest or eruption; that consider the diversity of parameters that could be used for analog identification; and that investigate the appropriateness of analog sets.   

Understanding volcanic impacts and how to reduce or manage their effects forms a cornerstone of volcanic disaster risk reduction. Multi-volcanic hazards occurring simultaneously and/or sequentially can be challenging to assess, as is managing the likely impacts. Volcanic ash, gas and acid rain are hazards which often occur together and collectively have the largest footprint of all volcanic phenomena: they are most likely to affect the greatest number of people. 

This session aims to explore how science can improve management of volcanic impacts through timely communication, field and laboratory-based assessment of impacts and mitigation measures, and the translation and application of this knowledge into volcanic risk management approaches. This includes exploring approaches to assess direct impacts of ashfall on communities (e.g., health, infrastructure, agriculture, transportation) and the longer-term effects of disruption (including ash remobilisation) as well as follow-up measures to communicate and better prepare communities. Ashfall impacts and mitigation measures are common to all explosive volcanic regions of the world and, thus, ongoing efforts are using global studies to populate and update public resources, such as the Volcanic Ash Impacts & Mitigation website and the International Volcanic Health Hazard Network website, in preparation for your next eruption.

We invite volcano scientists, city and emergency managers, environmental monitoring agencies and health professionals to work together to: 

• Share current knowledge and new research concerning impacts and mitigation resources for ash, gas and acid rain. 
  
• Share case studies of recent eruptions where civil authorities grappled with the combined impact of ash, gas, and acid rain, exploring key lessons and implications for best practice.
  

This session is sponsored by the IAVCEI Cities and Volcanoes Commission, International Volcanic Health Hazard Network, and the Volcanic Ashfall Impacts Working Group.

• understanding the state of dormant volcanic systems and the probabilities of renewed unrest and/or eruption
  
• geophysical and geochemical monitoring for evidence of unrest
  
• developing scenarios or probabilistic impact assessments
  
• understanding community risk perceptions and responses to forecasts
  
• enhancing preparedness and/or adaptation
  
• developing innovative educational programmes
  
• co-production of knowledge between scientists, indigenous peoples, emergency managers, and/or communities at long-dormant volcanoes. 

The SW Pacific is geologically complex consisting of a series of active and dormant oceanic island arc and back-arc systems that have undergone numerous phases of activity. The late-Tertiary and the Quaternary has seen periods of intense tectonic activity in the region, particularly in Fiji, Tonga, Papua New Guinea, Vanuatu and the Solomon Islands with frequent volcanic activity being experienced. To the north, the Samoan Islands, a series of youthful volcanic seamounts has also experienced periods of volcanic activity. Explosive and effusive volcanic activity has occurred in most of the countries, and is still continuing today. Associated with this activity; a range of volcanic hazards have affected many local communities. How then, can the small nations of SW Pacific best position themselves for coping with future volcanic disasters, and increase their resilience, particularly at the local community level? The region also offers a less traditional approach to studying volcanic hazard, risk, and risk management in the form of stories and oral history. Data derived from oral history, sits alongside scientific data and allows opportunities for inclusive working with indigenous people.
We invite papers that outline what work has been done or being undertaken in the SW Pacific region. Papers would include studies of individual volcanic systems and their activity, the status of the risk mechanisms within the region and volcanic hazard risk solutions that could or have been be used to reduce the risk to communities in the region form future activity.  

Geodetic data are a critical component of understanding volcanic unrest. Both deformation and gravity monitoring data at multiple spatial and temporal scales are available for hundreds of volcanoes worldwide.  Here we invite presentations discussing broad applications of volcano geodesy to global volcanoes, but also studies of individual systems that can have implications for understanding volcanic processes through development of improved techniques, integration of multidisciplinary data or modeling, and impacts on forecasting volcanic activity.

Although most prominent at divergent plate boundaries, interactions between magmatic and tectonic processes occur in all volcanic regions across different tectonic settings (compressional, extensional and strike-slip). Magmatic-tectonic interactions occur at different temporal and spatial scales, from short-term (days to years) interactions between magmatic systems and earthquakes on nearby faults, to long-term (kyr to Myr) lithosphere-scale interactions between stresses, tectonic structure, and magmatism. 

Feedbacks between tectonics and magmatism can influence the timing, style and location of volcanism, faulting, and geothermal systems. Deciphering these feedbacks allows informed interpretations of volcano unrest and seismo-tectonic activity. Examples of interactions between magmatic and tectonic processes include: (1) static and dynamic stress transfer leading to triggering or destabilising effects (e.g., earthquakes triggering volcanic eruptions or vice versa); (2) the influence of magmatic fluids in overpressure and in earthquake generation; (3) the combined influence of gravity, tectonic structure, and magma transport on surface stability and caldera collapse; (4) tectonic structure, stress regime, and lithosphere rheology impacting magma transport, eruption volume and style, and the long term evolution of a volcanic system; and (5) the influence of magma-tectonic processes on volatile flux and fluid circulation (e.g., hydrothermal fields). 

In this session, we solicit contributions exploring the interactions between magmatic and tectonic processes, particularly multidisciplinary studies that integrate volcanology, structural geology, geodesy, geochemistry, seismology, numerical and analogue modelling. 

Intraoceanic arcs represent one of the most important interfaces between the Earth’s interior, surface and atmosphere. As a result of tectonic plate processes oceanic plates are subducted, metamorphsed and devolatilized, resulting in melting of the mantle wedge and volcanic arc magmatism at the Earth’s surface. Arc magmas are a product of multiple components derived from the subducting slab and ambient mantle, with relative contributions from each varying significantly from the arc front to the backarc.

For this session, we invite contributions from relevant fields of geosciences that study tectono-magmatic and volcanological processes in convergent margin settings with a focus on the Eocene to recent Tonga-Kermadec-arc Lau-Havre-backarc system north of New Zealand. We aim at a multidisciplinary session to provide a holistic perspective on magmatism at subduction zones.

The near-surface environment in volcanic provinces is a dynamic place. Volcanic eruptions produce deposits that episodically cover the surface, while intrusions cause localized uplift. Constructional topography guides mass wasting and the pathways of water and/or ice, while the frequency and magnitude of volcanism controls erosion efficiency as a function of magmatic style. Basaltic lava flows are initially permeable and armor the surface to fluvial erosion, but are highly geochemically reactive. More inert silicic tephra can increase sediment transport and erosion rates, or flatten topography for super eruptions. Beneath the surface, deviatoric stresses associated with magma transport as well as climate and tectonics can be significant enough to modulate subsequent magmatism. The near-surface temperature field can differ significantly from a globally averaged geotherm. Both stress and temperature influence surface topography through time. Interpreting volcanic landscapes requires integrating episodic eruptions and intrusive magmatic uplift with pre-existing topography and geology, erosion by rivers and glaciers, biota, and regional tectonics. We are interested in submissions that explore volcanic-landscape interactions on any scale. This includes magmatic landscape construction and erosion, post-eruption environmental recovery, fluvial and hillslope response following sequences of eruptions, glacier-volcano interactions, volcano ecology, and any other connection between the surface environment and volcanic systems.  

Cenozoic volcanism in Antarctica and the Southern Ocean is an important part of the geological and palaeoenvironmental record. At least six active volcanoes and dozens of major volcanic centers are exposed in Antarctica and surrounding oceans. One of the best known, Erebus volcano, has a persistent phonolite lava lake and has been the site of extensive volcanological and geophysical studies for over 45 years. The hazard of effusive and explosive volcanism to life and logistics in Antarctica, from both active and dormant volcanic centres, is still poorly understood. Further, remote sensing has identified over 80 subglacial volcanic vents in West Antarctica. Igneous petrology aids in understanding the driving mechanisms of Antarctic’s tectonic development, and fundamental knowledge of mantle properties beneath the Antarctic Plate are revealed through the integration of geochemical and geophysical data sets. Important aspects of past ice sheet conditions, such as ice thickness and thermal regime (ice sheet stability), are best answered by looking at lava—ice interactions in a field of study known as glaciovolcanology. Ice cores provide valuable climate records extending back for 800 ka; they have an extensive tephra and aerosol record. The ice cores and exposed blue ice patches (some over 2.5 Ma old) use the volcanic data in constraining the age of palaeoenvironmental information recorded in the ice, understanding the environmental impact of volcanism and recording large- to global-scale eruptions.
This multidisciplinary session will be open to presentations on all aspects of Antarctic and Southern Ocean volcanism and will include, but not be limited to, the following topics:

• Tephra records 
  
• Relationship of volcanism to tectonic history 
  
• Nature and petrology of volcanic rocks 
  
• Mantle dynamics and sources of volcanism
  
• Activity associated with Erebus volcano lava lake
  
• Remote and geophysical studies of volcanoes 
  
• Glaciovolcanology 
  
• Volcanic hazards and monitoring  
  

Volcanoes inject abundant quantities of gaseous species and aerosols into the atmosphere during quiescent degassing and eruptive events. These emissions are predominantly composed of H2O, CO2, sulfur compounds and hydrogen halides, coexisting with  volatile trace elements and metals. More broadly, the chemical composition and mass flow rate of volcanic gas emissions vary with a number of parameters, e.g. chemistry and initial volatile content of the magmas, the P-T-redox conditions and dynamics of magma degassing processes, and the extent of interactions with volcanic hydrothermal systems. Given the key influence of the magmatic gas phase upon the dynamics of magma ascent and eruption, monitoring volcanic emissions at the surface has become one important approach to understand how volcanoes work and to forecast eruptions in complement to seismic and geodetic survey. Furthermore, measuring the emission rate of volcanic volatile species can provide important constraints on the size of magma bodies, as well as being of crucial interest to quantify the impact of volcanism upon the atmosphere and global geochemical cycles. 
Today a great variety of instrumental tools are being operated to study and survey volcanic gas emissions from the ground, air (e.g. drone-based), and space. In particular, short-term and long-term survey of volcanic degassing are possible by using in situ multi-sensor (e.g. MultiGas) devices and remote sensing tools working at a high temporal resolution in both the IR and UV spectral domains. In this Session we invite contributions covering all aspects of recent studies and monitoring of volcanic gas emissions, aimed at better understanding magma degassing processes, at forecasting eruptions and quantifying the impact of volcanic emissions upon the atmosphere. We welcome contributions discussing how novel measurement techniques, including ground- and space-based observations, and modeling studies of volcanic degassing provide new insights into volcanic processes and atmospheric impacts at local and global scales. 

Mass-wasting in volcanic environment comprises a wide spectrum of phenomena, from lateral collapse to shallow debris remobilization, representing a major threat for societies. Slope instability can affect volcano edifices and their surroundings on different time scales; slow onset phenomena characterize long-term continuous movements, whereas fast onset events comprise sudden and catastrophic events. Interpretation is challenged by complex interactions between tectonic, magmatic, fluid, and gravitational processes. Moving masses behave in different ways, depending on water content and flow rheology, from flank spreading or collapse to granular or viscous flow. Many volcanoes are located in high-precipitation environments or are covered by snow or glaciers, which exacerbates the potential for landslides, lahars and debris avalanches. Melting of snow and ice can generate flood of water that can be converted to a lahar through the incorporation of granular material. The encounter with a river or an excessive rain can progressively dilute the flow to a hyper-concentrated streamflow. At volcanoes located at or in the marine realm, slopes continue below sea level and also subaqueous volcano flanks can be prone to mass wasting, often affected by terrestrial volcano built-up and activity. All these events potentially cause severe damage to society, directly or indirectly through secondary events like tsunamis. Successful strategies for mass-wasting hazard assessment and disaster risk reduction would imply integrated methodology for instability detection, mapping, monitoring and forecasting. 

This session invites research efforts that observe, quantify, or model volcano slope movements and failure. We encourage multidisciplinary contributions that integrate field-based on-shore and submarine studies, geomorphological mapping and account collection, analysis of the formation and transport of granular and dilute flows through fluid mechanics and sediment mechanics application, with advanced techniques, as remote sensing data analysis, geophysical investigations, ground-based monitoring systems and numerical and analogical modelling of volcano spreading, slope stability and runout volcaniclastic flows. 

A major societal application of volcanology is to give an early warning of volcanic activity to reduce risks to communities. Magmatic processes occurring at depth within volcanic plumbing systems prior to, during, and after eruptions play a fundamental role in controlling the tempo and style of volcanic activity. Investigating these processes can thus lead to improved volcanic hazard assessment. These dynamic processes operate and interlink on scales of millimetres to kilometres, occur at timescales from seconds to hundreds or thousands of years, and involve complex physics and chemistry at the interface between fluid and solid mechanics. In recent years the concept of transcrustal magmatic systems has emerged to explain the temporal and chemical connection and evolution of upper crustal magma reservoirs to their lower crustal roots. Understanding the dynamics and linking the scales of processes throughout the transcrustal magmatic system is crucial to forecast its evolution towards eruption, and consequently providing accurate hazard and risk assessments. 

This session targets scientists dealing with the physical, chemical and temporal evolution of volcanic plumbing systems by using field, geophysical or geodetic observations, theoretical or analytical models, petrological and geochemical constraints, and experimental or numerical methods. 

To trigger cross-disciplinary interactions, the session aims are process-oriented and targeted at e.g.:

• studies of solidified, eroded volcanic plumbing systems; 
  
• pre-eruptive partial melting and magma generation, magma accumulation, mixing and migration of active volcanic plumbing system;
  
• petrological, geodetic and geophysical reconstructions of pre-eruptive magma storage and ascent conditions, and their combination; 
  
• simulations of magma storage, reservoir growth and/or transport using analogue and/or numerical modelling.    
  

This session is associated with the IAVCEI commission on Volcanic and Igneous Plumbing Systems (VIPS).   

Revealing the volumes, mechanics, chemistry, and temporal evolution of magma bodies in the Earth’s lithosphere, and how they contribute to its architecture and dynamics requires integration of multiple types of observations, and cross-disciplinary collaboration among geologists, geochemists, petrologists, geochronologists, volcanologists, and geophysicists. We aim to bring together researchers from across these disciplines to probe questions such as how do we:

• detect magma bodies and determine their volume and geometry
  
• quantify time-integrated chemical, mechanical, and thermal processes
  
• determine the frequency of magma injections, dykes, and melt extraction events
  
• interrogate minerals, glasses/melts, and volatile emissions, to constrain the timescales and location of magmatic processes
  
• decipher signs of volcanic unrest with respect to magmatic processes.
  

We encourage researchers that study magmatic processes using field studies, geophysical observations, laboratory analysis, modelling, and/or experimental simulations on any scale to submit contributions to this session. 

Inferring the spatial and temporal stress evolution of magmatic systems, and associated magma dynamics, inherently requires the use of modelling to link monitoring surface observations to subsurface processes. Advances in computing power, coupled with improvements in the understanding of magma plumbing systems and the spatiotemporal resolution of monitoring data have enabled the development of a new generation of geophysical and geodynamic models. New models have led to better constraints on the location, volume, rate, timing and mechanisms of magma supply, storage, and failure (amongst others), and provide critical advances for eruption forecasting and hazard assessment. In this session we will explore the current and future capabilities of numerical models for constraining the stress evolution in magmatic systems. We invite contributions including, but not limited to:

• Numerical model interpretations of surface deformation, gravity changes, and/or seismicity during volcanic unrest;
  
• Conceptual and theoretical studies testing the limitations and sensitivities of model approaches;
  
• Estimates of magmatic stress failure conditions;
  
• Numerical approaches for forecasting eruptive activity;
  
• Emerging technologies and methods;
  
• Investigations addressing the broad evolution of trans crustal magmatic / mush systems.  

Hazard assessments at many volcanoes are often hampered by incomplete or poorly preserved near-source eruption records due to their burial or destruction by younger explosive activity, erosion and weathering. While evidence of large magnitude eruptions can be lost from the geological record, mid- to low-intensity explosive eruptions are most susceptible to under-recording. Gaps in the near-source volcanic record make it difficult to accurately reconstruct the eruption history of a volcano, and in particular to reliably evaluate frequency-magnitude relationships over extended timescales. 

Distal to volcanic source, tephra layers preserved in long-continuous sedimentary archives (lacustrine, marine and peat), and even the polar ice cores, all used for palaeoclimate research, provide comprehensive records of explosive volcanism, particularly when fully integrated with proximal-medial eruptive successions. While these tephra layers are routinely utilised as chronological tools to aid palaeoclimate reconstructions, many of these archives are independently well-dated (e.g., 14C, annual layer counting) providing high-precision chronological constraints on the timing and frequency of activity at individual volcanoes. Constraints on the magnitude of past eruptions can be established by mapping the distribution and thickness of tephra deposits across suites of sedimentary records and developing regional tephrostratigraphic frameworks. 

Thus analysing tephra in these archives can provide crucial constraints on the scale, tempo and ash dispersals of past explosive volcanism, including useful insights into areas repeatedly impacted by ash fall and pyroclastic flows. These tephra repositories also provide key insights into the long-term chemical evolution of volcanic centres, and how this relates to the scale and timing of explosive volcanism. In this session, we welcome contributions that focus on using the tephrochronology of terrestrial, marine and ice core archives to construct more reliable eruption histories, to better understand eruption processes and past ash dispersals and those that use this information to aid more accurate volcanic ash fall hazard assessments.   

Large collapse caldera-forming eruptions present a significant risk to humans at a global scale. Such eruptions have only been recorded through careful investigation of the pyroclastic deposits left behind, and in the case of the extreme ‘supervolcanic’ event, the last one to occur was in New Zealand ~25 thousand years ago. The pursuit of understanding caldera systems and the threat they pose to society have been ongoing for decades, but in more recent years there have been significant strides in characterizing collapse calderas through interdisciplinary geological, petrological, geophysical, and numerical modelling research. In particular, there has been an increasing focus on timescales of geologic and petrologic processes associated with volcanic unrest, and innovative geophysical techniques employed to monitor and image large restless calderas and their magmatic plumbing systems. Both the scientific and societal importance of caldera unrest research is apparent with several active multi-agency, multi-national programmes focusing on large calderas worldwide (including Aira, Santorini, Campi Flegrei and Taupo) and potential future calderas (i.e. Laguna del Maule). We invite contributions focused on scientific findings that can be used to better characterise the hazard and risk of a future large collapse caldera-forming eruption. We would like to encourage abstract submissions of an interdisciplinary nature and/or fit into the following thematic categories:

• Multicyclic calderas- evolution of the magma system before, during and after caldera-forming eruptions
  
• Defining magma in an eruptible state
  
• Architecture of shallow magma reservoirs or magma bodies
  
• Crustal conditioning associated with enormous volumes of shallow magma
  
• Timescales and processes (magmatic and/or tectonic) leading up to or initiating eruption (i.e. when does unrest become eruption?)
  
• Defining and monitoring unrest through geophysical observations
  
• Unravelling the duration (days, months, years, decades) of caldera-forming eruptions through careful field and laboratory observations
  

Explosive volcanic eruptions are driven by rapid degassing of viscous magmas rising in the conduit and often produce substantial and sustained eruption columns (plumes).  While stable plumes may reach heights of several tens of kilometers into the atmosphere where they spread laterally as a gravity current, unstable plumes partially or entirely collapse to produce ground-hugging pyroclastic density currents. The spectrum of plume behaviours exert a fundamental control on the volcanic risk and impacts on environment and society.  For example, stable plumes are associated with reduced proximal risks but increased risk of shutdown of major aviation routes, and when the plume reaches the stratosphere, seasonal to multi-decadal impacts on climate.  The particle size distribution is initially determined by fragmentation processes in the conduit and then modulated by ash aggregation and reactions between ash particles, and volcanic and atmospheric gases entrained into the plume.  The stability and longevity of volcanic plumes is governed by a range of complex dynamics including the evolution of the size distribution of particles in the erupted mixture and also, crucially, the turbulent entrainment of atmosphere into the eruptive column which may itself be strongly affected by the particle size distribution.  These complex interactions and feedbacks have a fundamental role in: i) determining plume stability, ii) determining proximal to medial tephra fall out, iii) serving as the starting conditions for pyroclastic density currents derived from plume collapse, and iv) determining the composition, phase and vertical distribution of gases and particulate injected by the column into the atmosphere.

We invite contributions on recent advances on the topics identified above, whether these be in the form of analogue or theoretical (numerical) modelling, field-based, remote-sensing studies or any combination of these.  

We invite contributions presenting field-constrained eruptive histories of volcanoes, calderas, volcanic clusters, or arc segments delineated through integrated geologic mapping, (tephro)stratigraphy, geochronology, and geochemistry.  We also invite contributions on spatial or temporal changes (or the lack thereof) in eruptive volume, composition, or other measurable parameters at volcanic centers, overcoming the challenges and limitations to field-based studies, and the use of alternative methods to understand eruptive histories. Multidisciplinary contributions are especially encouraged.

Eruption histories are fundamental for understanding individual volcanoes and providing context for hazard assessment and mitigation, monitoring, and research.  Volcanoes are typically built over tens to hundreds of thousands of years and this record is the best guide to future behavior.  Developing comprehensive histories of active centers requires integrating (tephro)stratigraphy, field and remote mapping, physical volcanology, petrology and geochronology to understand the timing, frequency, duration, and diversity in eruptive style. Many volcanic centers lack even the most basic knowledge of their past eruptions or distribution of the resulting deposits. Even in the best cases, a volcano’s detailed eruptive history is limited by preservation, often biasing the geological record toward larger-scale eruptions. When a poorly characterized volcano reawakens, time and safety often preclude field-based studies, forcing reliance on modeling, analog volcanoes and expert elicitations to forecast the range of possible behaviors and hazards. While such methods are useful, each volcano has its individual characteristics and using proxies introduces a high level of uncertainty. Often, the number of analog volcanoes with well-characterized eruption histories is also limited. Delineating eruption histories in advance of unrest decreases uncertainty and increases the number of potential analogs available during crises at uncharacterized volcanoes.

The morphology of volcanoes and volcanic terrains contains inherent information on the wide range of geologic and geomorphic processes that construct and degrade them. Currently, a wealth of sources is available to study and quantify the morphology of volcanoes. In particular, digital elevation models (DEMs), generated from a variety of platforms and with increasing resolutions and spatial coverages (of the Earth, including the submarine and subglacial environments, and of the extraterrestrial planets), allow for detailed morphometric analysis not only of volcanic edifices but also of their individual depositional units. Geomorphological analysis can offer insight into the many aggradational and destructive processes that interact in the volcanic environment, enabling quantification of the growth and evolution of volcanoes, as well as the influence of other main agents such as tectonism and climate. This session aims at integrating and discussing the current state-of-the art of volcano geomorphology and morphometry, and welcomes contributions on:

• Quantitative-based classifications of volcanic landforms
  
• Growth and/or degradational histories of volcanoes, focusing on their morphometric evolutions with time
  
• Geomorphic analysis of the emplacement processes of lava flows, lava domes, scoria cones, maars, calderas and mass flow deposits
  
• Analysis of patterns and rates of erosion of volcanic landforms and the relation with climate
  
• The links between volcano morphometry, the spatial distribution of vents, the magmatic plumbing system, and the tectonic setting
  
• Methodological aspects, including evaluation of new datasets or DEMs, GIS routines to characterize volcanic landscapes, generation of new algorithms and application of new methodologies for morphometric studies of volcanoes
  
• Analogue and numerical modeling studies focusing on the geomorphology and morphometry of volcanic processes
  
• Field-based techniques and studies that quantify volcano morphology
  
• The role of geomorphology and morphometry for assessing volcanic hazards
  

Volcano geodesy has grown into one of the major pillars of volcano surveillance and research, with tremendous utility for the assessment of volcanic hazards and understanding of subterranean magmatic processes. Surface deformation and gravity change provide insights into the location of subsurface magma reservoirs, their volumes, and their changes over time, which relate directly to the potential for future eruptive activity. Geodesy thus has a strong role to play in the interpretation of volcanic unrest, as well as investigating the magmatic and tectonic structure of quiescent volcanoes and the characteristics of hydrothermal systems.  In addition, geodetic data are increasingly used in a number of non-traditional ways, for example, detecting ash plumes and mapping lava flows. 

We encourage contributions that make use of geodetic datasets to better understand volcanic processes and associated hazards, including: 

• Observations and interpretations of geodetic change at restless and erupting volcanoes and active hydrothermal systems    
  
• Insights into quiescent volcanoes based on geodetic investigations    
  
• New geodetic techniques and instrumentation    
  
• Methods for exploiting the ever-increasing volume of volcano geodetic data    
  
• Non-traditional uses of volcano geodetic data    
  
• Application of geodetic data to volcanic hazards assessment, also taking into account the temporal scales of the different geodetic techniques     
  
• Multidisciplinary studies that merge geodetic and other datasets    
  
• Studies of variable scales of volcano geodetic change, from individual eruptive vents to entire volcanic arcs 
  

Igneous processes on Earth produce large amounts of highly evolved, low-density magmas that form stable continents, feed ore deposits, and lead to supereruptions. Better understanding processes that lead to the generation and accumulation of such large silicic magma bodies remains one of the grand challenges of the earth sciences, and requires a multidisciplinary approach that integrates field work, geochemistry, geochronology, experimental petrology, geophysics, and numerical modelling on both volcanic and plutonic lithologies. With this session, we aim to gather researchers from all those different branches of our science, and provide a forum to discuss present ideas and plan the future in our pursuit to decipher processes that are controlling large silicic magmatic systems.     

Topics include but are not restricted to:

• Physical properties of multi-phase magmas
  
• The configuration of magma storage and plumbing systems in space and time
  
• The plutonic-volcanic connection
  
• Cycle of activity at calderas, and recurrence intervals between eruptions
  
• The influence on magma chambers and conduit processes on eruptive styles
  
• Deformation mechanisms in magmas and host rocks during emplacement and eruption
  
• Thermal evolution of magma reservoirs and the interaction with crustal lithologies
  

We would like to solicit in particular interdisciplinary studies investigating the chemical and physical evolution of magmatic systems by integrating of experimental- and/or modelling results with field- and/or analytical data. 

• Physical properties of magmas and lavas (pure melt to multiphase suspension and mushes)
  
• Rheological, thermal, chemical, petrological and textural evolution of magma during storage and transport.
  
• Timescales of magma assembly, storage and ascent.
  
• Deformation mechanisms in magmas and host rocks during emplacement and eruption.
  

Melt inclusions (MIs) are small pockets of typically silicate melt, which become trapped inside crystals as they grow from a magma, providing a unique sample of the melt from the magmatic system. Suites of MIs are often used to reconstruct the volatile budget and degassing history of volcanic eruptions, as the mineral host acts as a pressure vessel, theoretically preventing post-entrapment modification of the volatiles. MIs can also be used to understand the conditions of ore deposit formation in plutonic systems, where the rocks are otherwise often highly altered at the surface. MIs can be difficult to analyse due to their small size, multi-phase componentry, and beam sensitive nature. Despite these challenges, there are a wide variety of existing and developing experimental and microanalytical techniques to quantify their compositions (element concentrations, isotope ratios, speciation/oxidation states, including diffusion profiles) and structure (size/type of phases). These data provide invaluable information on the changes in composition prior to eruption during magmatic processes when combined with experimental petrology and computer modelling. Unfortunately, it is becoming increasingly evident that various post-entrapment processes (e.g., crystallisation, bubble formation, and diffusion) change the composition and structure of MIs, which requires new methods for MI treatment and data collection/reduction. This session aims to bring together topics relating to the utility of MIs in elucidating the magmatic processes occurring prior to eruption and in relation to ore deposit formation. These include experimental studies on volatile and melt evolution prior to eruption, post-entrapment effects and how to reconstruct MI composition/structure, as well as new analytical techniques. We also welcome studies of natural MIs (especially those including complementary datasets, e.g., geophysical, experimental, diffusion chronometry, etc.) to understand plutonic and volcanic systems, from the generation of ore deposits to understanding eruption triggers and, more generally, the architecture of magmatic plumbing systems. 

Many volcanological systems provide a wealth of spatially and/or temporally linked data. Such data can be as simple as vent locations, or almost too complex such as geochemical signatures, grain sizes, morphology etc. These data may be at the scale of a single eruption, or the entire Quaternary. 

There is a commensurate range of models available, based on techniques as varied as multivariate analysis, point processes, control charts and Bayesian computation. Techniques such as artificial neural networks, machine learning approaches and cluster analysis are gaining prominence in geoscience disciplines. The appropriate use of these statistical tools can leverage the broad range of data into insights that refine and develop our understanding of volcanic systems.

In this session we welcome all contributions that illustrate the novel application of statistical analysis to volcanic data which provide insights into some aspect of the volcanic system. Contributions that test, evaluate and/or compare different analysis approaches are particularly welcome.   

Volcanic eruptions impact Earth’s climate and environment on a range of temporal and spatial scales. Large volcanic eruptions cause global cooling, and can affect key modes of climate variability, such as the North Atlantic Oscillation, El Niño, and monsoon systems.  Since the beginning of the 21st Century, a series of smaller eruptions have significantly increased the stratospheric aerosol background and may have slightly slowed the rate of global warming.  Efforts at climate prediction on seasonal, annual, and decadal scales need to incorporate the effects of volcanic eruptions in their prediction schemes along with oceanic interactions to produce skillful forecasts. In addition, in a rapidly changing climate, it is important to understand how climate change may affect processes that govern volcanic impacts on climate and societies, such as the frequency-magnitude distribution of eruptions, the dispersion of volcanic ash and gas, or the chemical and microphysical processes controlling the lifecycle of volcanic aerosol particles and their radiative effects.

This session welcomes papers on the broad range of effects of volcanic activity on weather, climate, and the environment. This includes, but is not limited to, i) studies improving our understanding of past climate-volcano interactions, such as the role of volcanic eruptions in the onset of the Little Ice Age; ii) plans and methods for incorporating observations and models to produce weather and climate forecasts following future eruptions, and iii) contributions showing evidence or building hypotheses on how climate change may affect volcanic eruptions and their climatic effects. We also welcome contributions focusing on the understanding of specific processes (e.g., remote sensing of eruptions, or the chemical and microphysical processes that govern the evolution of volcanic aerosols) and on the societal relevance of climate-volcano interactions. 

Volcanic systems are a common source of heat that may represent an important potential target for geothermal exploration purposes. In particularly, the study of calderas is of great relevance because these volcanoes consist of large volcanic structures (with depressions usually larger than 2 km in diameter) associated with voluminous magmatic reservoirs that have protracted residence times. The finding of the most favorable thermal conditions in calderas to develop a long-lasting geothermal reservoir is a challenging task that requires a solid geologic knowledge based on a comprehensive integration of their volcanologic, magmatic and structural evolution in order to reveal their internal structure and unravel the evolution of the magmatic plumbing system and the permeability conditions that allow the ascent of hot fluids to the surface. Regardless of the large number of contributions on this field, we recognize it is far to be well understood, and therefore we still need to learn how the associated geothermal system is originated and developed through time. 

Many magmatic systems have the potential to provide a sustainable source of geothermal energy, a clean, low-carbon footprint, and cost-effective source of renewable energy. Economic extraction of geothermal heat in these systems depends on a combination of variables that include water recharge, reservoir permeability and access to the heat source. Characterizing and quantifying the interplay between these variables is essential for geothermal energy development and sustainability. While providing a sustainable source of energy, heat extraction in geothermal systems must include mitigation of potential environmental impacts and risk assessments associated with geothermal plant operations.

This session will cover a broad range of topics, including, but not limited to, techniques used to characterize and quantify geothermal resources, models of heat and mass transfer, spatial and temporal characteristics of reservoir permeability, delineation of geological structures, resource management, environmental and/or societal impacts, direct geothermal use, community outreach and hazards associated with geothermal energy production. The goal of this session is to bring together scientists from a range of disciplines (e.g. geology, geophysics, geochemistry, numerical modelling and resource management) to discuss challenges to, and/or advancements in, process-based understanding, technologies, resource management and sustainability of geothermal systems.

Worldwide research endeavours are exploring the potential for targeting and harvesting geothermal energy from greater depths and temperatures. Volcanic provinces offer the greatest potential to encounter unconventional geothermal resources where temperature or temperature and pressure conditions exceed the critical point of water (supercritical fluids) at shallow depth in the Earth’s crust as evidenced in several active geothermal systems worldwide including Krafla, Nesjavellir and Reykjanes (Iceland), The Geysers and Hawaii (USA), Lardarello (Italy), Los Humeros (Mexico), Menengai (Kenya), Kakkonda (Japan). These resources could generate an order of magnitude more energy per well than from conventional geothermal reservoirs. While some current projects focus on utilizing supercritical fluids some others explore the possibility of drilling into magma directly. In this session we are welcoming abstracts looking at increasing scientific knowledge of the magmatic-hydrothermal transition in order to better understand future geothermal resources as well as magmatic and hydrothermal processes. 

Volcanic activity - from passive degassing to effusive and explosive eruption - affects the environment on a range of spatial and temporal scales. The emissions of gases, aerosols, tephra and lava can have direct and indirect effects, potentially involving complex interactions and feedbacks within and across different environmental compartments. Ongoing interdisciplinary research to describe these effects, to unravel their underlying controls and mechanisms, and to predict their wider implications is essential to improve understanding of the links between volcanism and environmental change. This session broadly welcomes studies on the acute or chronic impacts of volcanic emissions (e.g., gases, aerosols, tephra, lava) within atmospheric, terrestrial and aquatic environments. This may relate, for instance, to processes influencing atmospheric composition (e.g., heterogeneous chemistry, cloud formation, ice nucleation) or biogeochemical cycling of elements (e.g., silicate weathering, soil carbon storage, ocean iron fertilisation). From large igneous provinces and super-eruptions of the geological past to various-magnitude events of the present day, we aim to bring together a wide range of researchers using field, laboratory and modelling approaches to better understand volcano-environment interactions, from local to global scales.