A mid to late Holocene cryptotephra framework from eastern North America
A mid to late Holocene cryptotephra framework from eastern North America
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DOI：
10.1016/j.quascirev.2015.11.011
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发表时间：
2016-01
影响因子：
4
通讯作者：
H. Mackay;P. Hughes;B. Jensen;P. Langdon;S. Pyne‐O'Donnell;G. Plunkett;D. Froese;Sarah E. Coulter;J. Gardner
中科院分区：
文献类型：
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作者：
H. Mackay;P. Hughes;B. Jensen;P. Langdon;S. Pyne‐O'Donnell;G. Plunkett;D. Froese;Sarah E. Coulter;J. Gardner
最近在北美东海岸约7000公里处发现了起源于阿拉斯加和太平洋西北部的全新世隐火山岩。这项研究扩展了新兴的北美火山灰年代学框架的地球化学特征17隐火山灰层从四个新勘探的泥炭地。所有检测到的火山岩沉积在晚全新世，没有地平线之间的泥炭。3000 -5000年前。阿拉斯加怀特河火山灰东瓣（公元847 ± 1年）的存在被确认为横跨纽芬兰到缅因州的东海岸，并提出了圣海伦山组W（公元1479-1482年）的区域沉积模式。首次出现的四个额外的cryptotephras在北美东部的描述，其中三个可能来自源区在墨西哥，堪察加半岛（俄罗斯）和北海道（日本）。这种火山岩到达北美东部的可能性提供了一个机会，可以将热带和东亚的古档案与西大西洋沿岸的古档案联系起来，有助于区域间对代用气候记录的比较。
Holocene cryptotephras of Alaskan and Pacific Northwestern origin have recently been detectedca.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 betweenca.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.