| Titre | Ocean-rafted pumice constrains postglacial relative sea-level and supports Holocene ice cap survival |
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| Auteur | Farnsworth, W R; Blake, W, Jr; Guðmundsdóttir, E R; Ingólfsson, Ó; Kalliokoski, M H; Larsen, G; Newton, A J; Óladóttir, B A; Shomacker, A |
| Source | Quaternary Science Reviews vol. 250, 106654, 2020 p. 1-13, https://doi.org/10.1016/j.quascirev.2020.106654  Accès ouvert |
| Image |  |
| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200529 |
| Éditeur | Elsevier Ltd. |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.quascirev.2020.106654 |
| Media | papier; en ligne; numérique |
| Formats | pdf; html |
| Région | Svalbard |
| Lat/Long OENS | 8.0000 31.0000 86.0000 76.0000 |
| Sujets | téphrochronologie; changements du niveau de la mer; plages soulevées; variations du littoral; sediments; pierre ponce; volcanisme; exploitation minière; résidus miniers; scorie; Calotte glaciaire;
géologie des dépôts meubles/géomorphologie; stratigraphie; géochimie; Nature et environnement; Sciences et technologie; Phanérozoïque; Cénozoïque; Quaternaire |
| Illustrations | cartes de localisation; graphiques; tableaux; diagrammes; représentations graphiques combinées |
| Diffusé | 2020 11 24 |
| Résumé | (disponible en anglais seulement)
Distally deposited tephra from explosive volcanic eruptions can be a powerful tool for precise dating and correlation of sedimentary archives and landforms.
However, the morphostratigraphic and chronological potential of ocean-rafted pumice has been under-utilized considering its long observational history and widespread distribution on modern and palaeo-shorelines around the world. Here we analyze the
geochemical composition and elevation data of 60 samples of ocean-rafted pumice collected since 1958 from raised beaches on Svalbard. Comparison of pumice data with postglacial relative sea-level history suggests eight distinct pumice rafting events
throughout the North Atlantic during the Middle and Late Holocene. Analyzed ocean-rafted pumice exhibit consistent silicic composition characteristic of deposits from Iceland's volcanic system, Katla. Eruption-triggered jökulhlaups are key drivers of
the transport of pumice from the Katla caldera to beyond the coast of Iceland and into the surface currents of the North Atlantic Ocean. Thus, the correlation of distinct, high-concentration pumice horizons from Katla deposited along raised Middle
Holocene beach ridges in Svalbard further advocates for the persistence of the Mýrdalsjökull ice cap through the Holocene thermal maximum. |
| GEOSCAN ID | 327564 |
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