Exmoor, Devon: The Tephrochronology Of Roman Lode
Author(s): Ian Matthews
A peat sequence from Roman Lode, Exmoor, Devon was investigated for the presence of microscopic volcanic glass shards (microtephra). Sampling of the 54cm sequence was undertaken at 1cm resolution and four discrete microtephra layers were identified. These layers were geochemically determined as being of Icelandic origin. The two youngest tephra layers were correlated with eruptions of Hekla in AD 1947 and AD 1510. A third tephra layer yielded few geochemical results and those that were obtained displayed three distinct geochemical signals. Tentative correlations are drawn between this tephra layer and the BMR-90 tephra (c. AD 920) though the data suggest that some of the shards have also been derived from the Torfajökull volcanic system. The oldest tephra layer was correlated with the OMH-185 tephra layer (755–680 cal BC, 2705–2630 cal BP; Plunkett et al 2004). Roman Lode is the only site in south-west England from which tephra layers have been identified and geochemically characterised. The data provide a preliminary Late Holocene tephrostratigraphy for the region. The potential for expanding tephrostratigraphical research in south-west England is briefly considered.
- Report Number:
- 26/2008
- Series:
- Research Department Reports
- Pages:
- 19
- Keywords:
- Tephrochronology
