Datation des moraines Holocènes d’Islande par tephrochronologie: un état de l’art

Tephrochronology utilises age-equivalent horizons of volcanic ash to correlate across landscapes. In Iceland, the proximity of active volcanoes to glaciers and ice caps enables tephrochronology to contribute to a reliably-dated reconstruction of later Holocene glacier advances. This paper reviews the principles and practice of terrestrial tephrochronology in the Icelandic context, supported by examples from recent research. Key issues which are reviewed include the contrasting responses of large ice caps and small mountain glaciers; the status of the “Little Ice Age” and in particular the timing of its maximum; the use of tephrochronology to test the reliability of lichenometry; and the issue of preservation potential and the representativeness of moraine-based chronologies in Iceland.