Welcome to the Commission on Collapse Calderas



NEWS 5/11/2019


The 8th Workshop on Collapse Caldera
September 2020, Santorini Caldera, Greece

Optional Short Course: 18-19 September
Main workshop: 20-25 September

The 8th Workshop of the IAVCEI Commission on Collapse Calderas, preceded by an optional short course (17 to 26 September 2020) This is the biennial Collapse Caldera Workshop (CCW); it will be longer and much broader in scope than the Explosive Volcanism-Tephra Hazards event, and will deal with all aspects of caldera volcanism, from the magmatic root to the marine environment and human population.
The two-day short course will accommodate 25 to 30 participants (including lecturers) and will cover such topics as the tectonic-magmatic settings of calderas, caldera eruptions and hazards, crustal magmatic systems beneath calderas, geophysical methods of sounding calderas, remote sensing of calderas, physics and structure of caldera systems, caldera unrest and monitoring, and caldera risk and resilience.
The workshop will accommodate the short-course participants plus an extra 20 to 25 (for a total maximum of 50 workshop participants). It will include three field days focussed on the evolution of Santorini, pyroclastic facies and their relationship to caldera formation, architecture and structure of a caldera volcano based on land and submarine records, the unrest of 2011-2012, and the unravelling of a caldera-forming eruption (Late Bronze Age) from its products (fallout, flows, juvenile, cognate and accidental components, petrology, chemistry). The field days will be led by T. Druitt, P. Nomikou and D. Pyle. There will be three days of senior scientist and student led presentations, breakout sessions, and brainstorming with the aim of planning a white paper on fundamental issues of caldera volcanism, unrest, and risk, and the strategies needed to address them (i.e. a multidisciplinary approach).
Short course participants would arrive on-island on 17 September, and the course would take place on the 18 and 19. Workshop-only participants would arrive on 19 September and the workshop would take place on 20-25, with all participants leaving on 26 September. The cost of the workshop would be about 750 euros, and that of the short course an extra 300 euros. These prices exclude travel to and from Santorini and may evolve slightly.

People potentially interested in participating (either short course plus workshop, or just workshop) are invited to contact Tim Druitt at
for further information.

First Circular (PDF)
20 Feb. 2020 released

NEWS 14/03/2019

The 7th Workshop on Collapse Caldera in Toba Caldera, Sumatra, Indonesia, Great success

The 7th Caldera Commission Workshop at Toba, 21 - 27 September, 2018, was a real success. The local organising committee, led by Shan de Silva, did a fantastic job at engaging the Indonesian Volcanology community and delivering a logistically flawless workshop. This was complemented by the stunning weather and scenery which made for some superb excursions inside and outside the enormous caldera. There were more than 60 workshop participants with an almost equal number of emerging and senior researchers from across the globe and Indonesia. An effort was made to have discussions around presented research and to highlight new and emerging directions, questions, and gaps in caldera research.

NEWS 13/12/2013

We are updating our member list

Please contact to the web mamager (Nobuo Geshi, geshi-nob@aist.go.jp) if you find problems in your name in the member list. Please contact the web manager if you wish to join CCC. You can see the member list from the tag in the left column.

Creation of the new IAVCEI Commission on Collapse Calderas (CCC) was approved by the Executive Committee and Secretary General of IAVCEI in March 2008.

The idea to file for a commission emerged in 2005, during a workshop on Caldera Volcanism, at which the Collapse Calderas Work Group (CCWG) was formed.

The commission is currently led by:

at a Castle in the Permian Ora caldera near Bolzano, Italy, sitting on an ignimbrite block

Guido Giordano

(Roma Tre Universita, Italy)


Darren M. Gravley

(Canterbury University, New Zealand)


Former Commissioners: Prof. Joan Marti, Dr. Joachim Gottsmann, Dr. Gerardo Aguirre Diaz, Dr. Adelina Geyer, Dr. Valerio Acocella, Dr. Nobuo Geshi, Prof. Shan de Silva

One of the first major events for the commission was the 2008 collapse calderas workshop in Mexico (Click for details)

The commission covers a wide spectrum of research topics and fosters common interests in research on collapse calderas such as geology, geophysics, numerical and analogue modelling, magma chamber processes, hazard assessment and risk management as well as economic and environmental aspects.

The commission epitomises the spirit of the original workgroup and provides a platform for interdisciplinary interaction to solve the many outstanding questions regarding the formation of collapse calderas, their evolution and behaviour, and for knowledge transfer to a wider audience.

At the same time, there is room for incorporation of additional lines of research in the future and these are more than welcome to add their flavor to the commission.


CCC Membership


Current commission members include renowned scientists as well as a number of young emerging researchers and recent graduates. More than 25 members formed the start-up commission and we are encouraging those interested in caldera research to join the commission.

Our commission is quite active and we want to keep growing, meeting, and willing to collaborate actively. We share a common drive to learn more on caldera volcanism and to publish new results of our research in high-class journals and books.

If you wish to become a member of the commission on collapse calderas please fill send an email to Nobuo Geshi, who is the current webmaster



Last update: Nov 11, 2019