Lookup NU author(s): Dr Helen Mackay
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
Holocene cryptotephras of Alaskan and Pacific Northwestern origin have recently been detected ca. 7000 km away on the east coast of North America. This study extends the emerging North American tephrochronological framework by geochemically characterising seventeen cryptotephra layers from four newly explored peatlands. All detected tephras were deposited during the late Holocene, with no horizons present in the peat between ca. 3000–5000 years ago. The prevalence of the Alaskan White River Ash eastern lobe (AD 847 ± 1) is confirmed across the eastern seaboard from Newfoundland to Maine and a regional depositional pattern from Mount St Helens Set W (AD 1479–1482) is presented. The first occurrences of four additional cryptotephras in eastern North America are described, three of which may originate from source regions in Mexico, Kamchatka (Russia) and Hokkaido (Japan). The possibility of such tephras reaching eastern North America presents the opportunity to link palaeo-archives from the tropics and eastern Asia with those from the western Atlantic seaboard, aiding inter-regional comparisons of proxy-climatic records.
Author(s): Mackay H, Hughes PDM, Jensen BJL, Langdon PG, Pyne-O'Donnell SDF, Plunkett G, Froese DG, Coulter S, Gardner JE
Publication type: Article
Publication status: Published
Journal: Quaternary Science Reviews
Print publication date: 15/01/2016
Online publication date: 10/12/2015
Acceptance date: 14/11/2015
Date deposited: 15/12/2015
ISSN (print): 0277-3791
ISSN (electronic): 1873-457X
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