VolcanologyMelbourne University, October 29, 2026
From 1pm onwards
|
Registration (Symposium Registration and Dinner RSVP)
Symposium Registration
|
Selwyn Dinner Registration
|
|
Participants can also register on site on the day. Cash payment only. Detailed Program
|
|
13.00 - 14.00
|
Registration (coffee and tea available)
|
|
14.00 - 14.05
|
Dr. Saini Samim / Professor Fabio Capitanio (GSAV Chair)
Symposium Opening |
|
14.05 - 14.30
|
Professor Fabio Capitanio, Monash University
Deep Roots: Volcanism, Depletion, and the Longevity of the Australian Continent AbSTRACT
Earth's volcanic history records the evolution of its tectonic regimes, yet how volcanism changed through time and what it reveals about planetary evolution remains poorly understood. Using numerical models of mantle convection, we show that volcanism is not merely a surface expression of mantle dynamics but an integral driver of the system. Large-scale Archean volcanism is coupled with the growth of deep continental roots: as melting produces thick, depleted and stiffened lithosphere, it drives the key transition from a mobile, recycling-dominated regime to the stable, durable continents we see today. This volcanic-tectonic-geodynamic coupling, and the melting history it generates, provides a direct proxy for mantle outgassing and atmospheric evolution, linking the deep interior of the planet to the long-term conditions that shaped its habitability. bIO
|
|
14.30 - 14.55
|
Dr. Saini Samim, Volcanology, The University of Melbourne
Tephra Tales from Turkana: From Dating Human Evolution to Decoding Volcanic Systems AbSTRACT
The Turkana Basin in northern Kenya, hosted within the East African Rift System, preserves one of the world’s most remarkable records of human evolution, interbedded with numerous layers of volcanic ash (tephra). These widespread tephra layers provide critical time markers for early human fossils, archaeological sites, and environmental records across the basin, while also preserving snapshots of volcanic activity and magmatic processes during milestone events in hominin evolution. In this talk, we explore the multiplicative value of combining high-resolution tephrochronological approaches, particularly 40Ar/39Ar geochronology and in-situ trace-element geochemistry, to refine this volcanic timeline and extract new insights from the tephra record. Beyond establishing when eruptions occurred, the chemical fingerprints preserved in volcanic glass and minerals can reveal connections between deposits, magma evolution, and the processes operating beneath volcanic systems. Together, these approaches transform tephra from geological time markers into detailed archives of volcanism, providing new perspectives on both the chronology of human evolution and the dynamic volcanic landscapes in which our ancestors lived. bIO
|
|
14.55 - 15.20
|
Dr Hayden Dalton, Argon Dating, The University of Melbourne
Unlocking the Timelines of East African Volcanism: Magmatic Longevity and Hominin Evolution AbSTRACT
Hayden Dalton¹, Saini Samim¹, Ashley Savelkouls¹, David Phillips¹, Rohan Anderson¹ ¹School of Geography, Earth and Atmospheric Sciences, The University of Melbourne, Parkville, Australia The East African Rift system hosts some of the most explosive and hazardous silica-rich volcanoes on Earth, yet the lifespans and evolutionary pathways of these magmatic systems remain poorly constrained. Focusing on volcanic deposits within the Turkana Basin, I will present findings from investigations into these gas-rich, large-volume explosive eruptions to better understand when they occurred, how they evolved, and where the magmas originated. By integrating single-crystal Ar-Ar geochronology of tuffs and pumice clasts with Bayesian age modelling, we can begin to resolve the complex age distributions preserved within the geological record. I will demonstrate how the remarkably wide array of single-grain ages reveals the protracted longevity of these magmatic systems long before they eventually erupted. Ultimately, a comprehensive understanding of these extended pre-eruptive timescales not only yields critical insights into the recurrence intervals of dangerous volcanic activity, but also provides an essential, high-resolution chronological framework to help refine the timeline of early human evolution. bIO
|
|
15.20 - 16:00
|
Afternoon tea break (coffee, tea and snacks available)
|
|
16:00 - 16:30
|
Professor John Webb, Latrobe University
The hydrogeology of the basalt plains of western Victoria AbSTRACT
The lava flows of the Victorian basalt plains have low porosity but often high fracture permeability, and contain large amounts of groundwater with very variable salinity. Fresh groundwater is mostly confined to young lava flows and the areas around volcanoes, and is often quite young (<50 years old), whereas very saline groundwater occurs beneath older flows and may be up to 20,000 years old. The salinity is mostly derived from rainfall concentrated by evapotranspiration in the soil, along with species released by weathering of the basalt. Basalt lava flows older than ~1 Ma are covered by thick, clay-rich, low permeability soils; as rainfall infiltrates through these, evapotranspiration removes most of the water and salt builds up in the soil and groundwater. In contrast, younger basalt flows have thin stony soils that allow rapid infiltration of rainfall, so there is less impact of evapotranspiration and the groundwater is fresh. Volcanoes often have permeable soils, particularly if they are scoria cones, and the fractured feeder pipes beneath them allow rapid downwards groundwater flow, so groundwater underneath volcanoes is generally relatively fresh. Lakes on the basalt plains are saline if they are sealed, so all salt input remains in the lake, or if they are supplied by saline groundwater discharge. Areas of dryland salinisation reflect shallow watertables (<2 m deep), where evaporation can concentrate the groundwater. The area affected varies with rainfall, but may have increased following European settlement due to large-scale clearing of native forest, resulting in increased recharge and rising watertables. bIO
|
|
16:30 - 17:00
|
Dr Heather Handley, Melbourne Museum
Australia's volcanic risk: Past impacts and the need for a comprehensive national assessment AbSTRACT
Australia is exposed to volcanic hazards from potential future eruptions of both domestic and international volcanoes, yet the nature, extent and magnitude of this risk have not previously been comprehensively assessed at a national scale. This knowledge gap limits the ability to anticipate volcanic impacts and support evidence-based emergency management and preparedness. This talk provides an overview of Australia’s volcanic risk by integrating geological, volcanological and historical evidence with long-standing cultural knowledge to demonstrate the need for a comprehensive national volcanic risk assessment. Australia’s volcanic risk extends beyond airborne ash impacts, encompassing atmospheric, marine and societal hazards. Historic international eruptions have affected Australia through volcanic ash, while volcano-generated tsunami and pumice rafts have reached Australian coastlines, causing social, economic and environmental impacts. Australians are also exposed to volcanic hazards overseas, highlighted by the 2019 Whakaari/White Island eruption, in which 17 Australians lost their lives. Domestic volcanic hazards are also under-recognised, with at least two mainland volcanic provinces in southeastern and northeastern Australia remaining potentially active. Mantle xenoliths preserved within erupted rocks and First Peoples oral traditions describing volcanism provide complementary geological and cultural insights into past volcanic activity, highlighting the possibility of future eruptions occurring with limited warning. Together, these examples demonstrate that Australia’s volcanic risk is diverse, geographically widespread and incompletely characterised. A comprehensive national volcanic risk assessment is needed to quantify hazard exposure, identify knowledge gaps and inform monitoring, emergency planning and preparedness. Such an assessment also provides an opportunity to use Australia’s volcanic geoheritage to communicate volcanic processes, past eruptions and future risks. bIO
|
|
17:00 - 18.00
|
Drinks and nibbles
|
|
18.00 - 19.00
|
Selwyn Keynote: Public Lecture
Associate Professor Teresa Ubide, Volcanology, University of Queensland “Under the volcano: Unveiling magma histories with microanalysis” AbSTRACT
Magma storage modulates the explosivity, frequency, and impact of volcanic eruptions, and controls the formation of magmatic-hydrothermal mineral deposits. The architecture of magma storage and plumbing systems, and their eruption triggering mechanisms, are inaccessible to direct observation in active volcanoes. However, they can be accessed through the erupted volcanic rocks and the crystal, melt, and gas records they contain. This seminar will explore novel micro-analytical techniques, including laser ablation mass spectrometry elemental mapping and isotope analysis, to interrogate volcanic rocks and their plutonic cargoes, aiming to better understand magmatic switches that drive volcanic eruptions and mineralisation in critical metals for the green energy transition. bIO
|
|
19.30
|
Symposium Dinner
Café Corretto, Lygon St, Carlton (registration required, additional cost) |
Convenors: Dr Anne-Marie Tosolini and Dr Saini Samim
