International Focus Group on

Tephrochronology (INTAV)


Welcome to INTAV, the International Focus Group on Tephrochronology and Volcanism. INTAV is a worldwide collective of geoscientists with a central interest in tephra (volcanic ash) studies and their application as a linking, dating, and synchronising tool in a wide range of disciplines including Quaternary stratigraphy, palaeoclimatology, palaeoecology, physical geography, geomorphology, pedology/palaeopedology, archaeology, geochronology, and also volcanology, including volcanic stratigraphy, volcanic petrology, and volcanic hazards and impacts. The word ‘tephra’ derives from a Greek word meaning 'ashes'. Tephrochonology refers to the use of tephras as a stratigraphic linking and dating tool but it is also used more broadly as a collective term for the study of tephras. People who study tephras and their application are referred to as tephrochronologists.

INTAV was formed as an international focus group (IFG) in 2007 at the International Union for Quaternary Research (INQUA) congress held in Cairns and is affiliated to that organisation and specifically as a group within the Stratigraphy and Chronology Commission (SACCOM). It replaced previous INQUA-affiliated groupings of tephrochronologists and volcanologists known as Sub-commission on Tephrochronology and Volcanism (SCOTAV), Commission on Tephrochronology (COT), and earlier groups dating back to 1961. The INTAV executive and >100 members believe strongly in the importance of tephrochonologists being connected through INTAV and its activities. INTAV has been reaffirmed as an IFG through to 2019. The new core project of INTAV (2015-2019), EXTRAS (“Extending tephras”), described in more detail elsewhere on the website, is to enhance tephrochronology as a global research tool and its application in multiple Quaternary disciplines and volcanology. This aim will be met through seven objectives that contribute to improving the methodologies of tephrochronology and thus, through chronostratigraphy, support and underpin many Quaternary projects as well as geochronological and volcanological applications.

As well as this website, news items are posted on our INTAV Facebook page from time to time, and also JISCMail-Tephra. Please feel free to join these to keep in touch with your international tephrochronological community.

The names and addresses of the current executive of INTAV are given. Please feel free to contact them about any matters relating to INTAV activities. To join INTAV, please enter ‘Tephra’ in the ‘Search’ box top right at Searchable archives of internet discussions on tephra studies are at

Contact addresses of the current executive INTAV 2015-2019


Professor Takehiko Suzuki

Department of Geography

Tokyo Metropolitan University

1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan

Vice presidents

Dr Victoria Smith

Research Laboratory for Archaeology and the History of Art
University of Oxford

Oxford OX1 3QY, UK

Dr Britta Jensen

Department of Earth and Atmospheric Sciences

University of Alberta
Edmonton AB, T6G 2E3


Dr Peter Abbott

Geography, College of Science

Swansea University

Swansea SA2 8PP, Wales


Immediate past president
Professor David J. Lowe

School of Science, Faculty of Science and Engineering
University of Waikato, Private Bag 3105
Hamilton 3240, New Zealand


From top: Karymsky, Kamchatka, Russia erupting in August 2006; Active Tephra meeting in Kirishima, Japan; glass shards in a core from Lago Grande di Monticchio, Italy; and tephra within the Tenjindan archaeological site, Kyushu, Japan.