Dating landscape change using tephrochronology
Funded by the Leverhulme Trust
Dave Bescoby with Julian Andrews, Jenni Barclay and Mike Leeder
By the end of the 5th Century AD, the Western Roman Empire had changed beyond all recognition, giving way to barbarian kingdoms that eventually developed into the modern European states of the present. While political, economic and militaristic factors, both localized and empire wide were an active part of this transformation, this was also a period of accelerated landscape change, particularly within the Mediterranean.
This project aims to address this problem by taking advantage of the volcanically active nature of the Mediterranean to construct what is known as a tephrochronology, capable of providing precise stratigraphic time markers within an observed sequence of changing palaeo-environments. Fine volcanic ash, including glass shards, pumice and lithic fragments are ejected high into the atmosphere during volcanic eruptions and are capable of traveling several thousand kilometers. Individual volcanic eruptions are characterised by unique geochemical fingerprints and can be identified through an analysis of their tephra, which is often preserved in former lake and wetland environments such as peat bogs. Many of the large volcanic eruptions occurring during the Roman period are precisely dated through historical sources, allowing the attribution of near-absolute dates.
Tephra found in a core from the Roman remains at Butrint, Albania. This tephra has the composition of a peralkaline rhyolite, probably sourced from a Mediaeval eruption from the Aeolian Islands, Italy.
The Roman remains at Butrint, Albania. Several cores have been taken from this site, with new remains in Greece being visited in 2006.
UEA Volcano page