Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.659956
Title: Ocean-transported pumice in the North Atlantic
Author: Newton, Anthony
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 2000
Availability of Full Text:
Access through EThOS:
Full text unavailable from EThOS. Please try the link below.
Access through Institution:
Abstract:
The aims of this study are to identify the sources of the widespread Holocene deposits of pumice found along the coasts of the North Atlantic region and the age of the source eruptions. Previous research has failed to positively identify the precise source of this pumice. Fieldwork is carried out in Norway and Iceland to obtain pumice pieces for geochemical analysis. Pumice pieces are recovered from Holocene raised beaches and the height of these deposits above sea-level determined. This establishes the existence of substantial local deposits of Holocene pumice on the raised shorelines of north-western Iceland for the first time. The fieldwork in Norway confirms the presence of multiple levels of brown/black/grey pumice on mid-Holocene Norwegian raised beaches and white pumice on late-glacial/early Holocene shorelines. Pumice is also collected from the slopes of the Katla Volcanic System, southern Iceland, which is identified as a possible source of the dacitic pumice. Archaeological pumice, donated by collaborators, from sites in the British Isles is also analysed. The number of archaeological sites where pumice has been recorded is nearly doubled to almost 150. A collaborative project identifies at least 17 silicic tephra layers (SILK layers) which have been produced by the Katla Volcanic System during the Holocene. Geochemical analyses are performed on the majority of these tephra layers. Over 1500 electron probe microprobe analyses (EPMA) and over 200 Secondary Ion Mass Spectrometry (SIMS) analyses are undertaken on pumice and tephra samples. These are the first high quality grain specific analyses carried out on pumice in the North Atlantic. These analyses establish that the majority of the mid- to late-Holocene pumice found in the study areas is dacitic and produced from the same source. Geochemically different and older pumice also occurs in Mesolithic archaeological sites in Scotland. All of the analysed pumice can be correlated to volcanic activity in Iceland.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.659956  DOI: Not available
Share: