International Focus Group on Tephrochronology


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.

Join INTAV – don’t miss out!
For those not familiar with INTAV, which represents a long-standing (nearly 60 years) international group of tephra specialists nominally under the auspices of INQUA, it is easy to become a member and to receive regular updates on events past and future. Please join us! In addition to the website, we have two main means of communication and you just need to sign up to one or the other, preferably both, to become a member of INTAV:

1. Facebook: go to

2. We have our own group home page, ‘Tephra’ as part of the UK-based JISCM@il, an ‘Email discussion list for the UK education and research communities’ (JISCMail TEPHRA): go to JISCMail and enter ‘Tephra’ in the search box).

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.

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 Britta Jensen
Department of Earth and Atmospheric Sciences
University of Alberta
Edmonton AB, T6G 2E3

Dr Peter Abbott
School of Earth and Ocean Sciences – Cardiff University
Institute of Geological Sciences – University of Bern
Present Address:
Baltzerstrasse 1+3
3012 Bern

Professor Siwan Davies
Swansea University, UK

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

Honorary life members

Every few years the INTAV executive confers honorary life membership on one or more tephrochronologists who have excelled in the discipline as practitioners or mentors or in some other way that deserves international recognition.

Gudrun Larsen (Iceland) and David Lowe (New Zealand) have recently been elected honorary life members of INTAV.

Currently, thirteen people have been awarded honorary life membership of INTAV:

James Begét (USA)
Andrew Dugmore (UK)
Valerie Hall (UK) (1946-2014)
John Hunt (UK)
Etienne Juvigné (Belgium)
Gudrun Larsen (Iceland)
David Lowe (New Zealand)
Hiroshi Machida (Japan)
Hiroshi Moriwaki (Japan)
Vera Ponomareva (Russia)
Andrei Sarna-Wojcicki (USA)
Colin Vucetich (New Zealand) (1918-2007)
John Westgate (Canada)
Ray Wilcox (USA) (1912-2012)





2010 Active Tephra meeting in Kirishima, Japan; from top Ito Ignimbrite, Aira Caldera, Kyushu, group photo with the Sakurajima Volcano, tephra within the Tenjindan archaeological site, Aso, Kyushu, Japan.