First discovery of Holocene Alaskan and Icelandic tephra in Polish peatlands

Abstract

Despite the discovery of cryptotephra layers in over 100 peatlands across northern Europe, Holocene cryptotephra layers have not previously been reported from Polish peatlands. Here we present the first Holocene tephra findings from two peatlands in northern Poland. At Bagno Kusowo peatland we identify the most easterly occurrence of the AD 860 B tephra, recently correlated to the White River Ash (WRAe) derived from Mount Churchill, Alaska. A shorter core from Linje peatland contains tephra from the Askja 1875 eruption, extending the spatial distribution and regional importance of this Icelandic tephra in Eastern Europe. Our research indicates the potential of cryptotephra layers to date and correlate the growing number of palaeoenvironmental studies being conducted on Polish peatlands and contributes towards the development of a regional Holocene tephrostratigraphy for Poland.

Rhyolitic and dacitic component of the Askja 1875 tephra in southern and central Finland: first step towards a Finnish tephrochronology

“…However, at the time no cryptotephra investigations had been performed beyond Sweden to define the eastward extent. Our study therefore both improves and refines the detected limit of the Askja 1875 tephra, and our data together with results from recent cryptotephra studies in the northern part of the European mainland (Hang et al ., ; Stivrins et al ., ; Tylmann et al ., ; Wulf et al ., ; Watson et al ., ) reveal a more complex pattern of tephra dispersal in the far‐distal area than previously assumed.…”

“…Previously published isopach maps propose that ash from the Askja 1875 eruption was first carried eastwards from Iceland until a southward shift in direction occurred above Scandinavia (Carey et al ., ). It is apparent from our data that tephra shard concentrations both in peat and in lacustrine sediment in Finland far exceed those encountered from sites in mainland Europe (Stivrins et al ., ; Tylmann et al ., ; Wulf et al ., ; Watson et al ., ), indicating that southward deflection of the ash plume above Scandinavia may not have been as strong as previously assumed.…”

“…These developments have led to a significant increase in routine cryptotephra studies across northern Europe in recent years (e.g. Wulf et al ., ; Timms et al ., ; van der Bilt et al ., ; Watson et al ., ). However, cryptotephra layers have not yet been identified in Finland, despite its favourable location in relation to transport pathways of Icelandic tephra, proven by the classic study of Salmi () that identified visible fall‐out of tephra from the Hekla 1947 eruption on the snowpack surface in southern Finland.…”

Traces of volcanic ash from the Mediterranean, Iceland and North America in a Holocene record from south Wales, UK

“…This finding lends support to the identification of the Aniakchak tephra in south Wales and is consistent with other examples of transatlantic transport of ash. The White River Ash eastern lobe, originating from Mount Churchill (Alaska), is found in a number of northern European sites including as far east as Poland (Jensen et al, 2014;Watson et al, 2017a), while traces of tephras originating from the Cascades (northwest America), have also been discovered at Finglas River, southwest Ireland, (Turney, 1998;Timms et al, 2019).…”

“…The majority of Holocene tephra deposits found in northwest Europe are of Icelandic origin; however, a number of recent studies have revealed the presence of glass shards that originate from 'ultra-distal' sources from across the Northern Hemisphere (e.g. Jensen et al, 2014;van der Bilt et al, 2017;Watson et al, 2017a;Cook et al, 2018). The first 'ultra-distal' discovery was the White River Ash eastern lobe, sourced from Mount Churchill, Alaska, and found preserved in peatlands in Ireland and Germany (Jensen et al, 2014).…”