Bazanova, L.

Cook, E.

Davies, S. M.

Ponomareva, V.

Portnyagin, M.

Svensson, A.

OceanRep

2017 AGU Fall Meeting https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/2777251 von 2 19.11.17, 17:40PP53A-1115: First identification of cryptotephra from Kamchatka in aGreenland ice core and new tephra links between distal climate recordsfrom Greenland and the northwest PacificFriday, 15 December 201713:40 - 18:00Our work presents new correlations between cryptotephra deposits found in Greenland ice cores and widespreadtephra layers found in terrestrial and marine records in the northern Pacific, providing: 1) a unique opportunity toexamine climate records in distal locations and 2) an independent assessment of radiocarbon dates and marinereservoir calculations, using ages derived from Greenland Ice Core Chronology 2005 (GICC05).Low concentrations of tephra grains from two well-known eruptions from northern Pacific Arc volcanoes have beentraced in the NGRIP and NEEM ice cores; the first from a Holocene eruption from Khangar volcano in the KamchatkaPeninsula (eastern Russia), and the second from an eruption during the late glacial/interglacial transition (LGIT) fromTowada in Japan. Correlations were based on the chronological position of layers and geochemical characterisationby EPMA and LA-ICP-MS to derive major oxide and trace element concentrations.In NGRIP the rhyolitic KHG tephra from Khangar volcano (western Kamchatka) has a GICC05 age of 7950 ± 41 yearsb2k and is located close to the termination of the 8.2 ka cold event that affected the Northern Hemisphere. KHG is akey terrestrial marker deposit in Kamchatka and is stratigraphically significant as it marks the end of this cold event inKamchatka in a number of records. This is the first finding of the KHG tephra outside Kamchatka and the firstconfirmed identification of any Kamchatka tephra in Greenland ice. Additionally, the correlation of a rhyoliticcryptotephra in found in NEEM and NGRIP to a widespread Japanese deposit, Towada To-H (15,706 ± 113 a b2k)represents the first long range tie-point to be established within the LGIT, creating an opportunity help validate localmarine reservoir effect calculations of cores containing To-H from the forearc terrace of the Japan Trench. Thefindings highlight the relevance of locating long-range, low-concentration cryptotephra deposits in well-dated ice cores.Plain Language SummaryAuthorsEliza Cook *Centre for Ice and ClimateVera PonomarevaInstitute Volcanology SeismolMaxim PortnyaginGEOMAR Helmholtz Centrefor Ocean Research KielLilia BazanovaAnders SvenssonCenter for Ice and Climate,University of CopenhagenSiwan Manon DaviesSwansea UniversityFind SimilarView Related EventsDay: Friday, 15 December 2017New Orleans Ernest N. Morial Convention Center - Poster Hall D-F2017 AGU Fall Meeting https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/2777252 von 2 19.11.17, 17:40

First identification of cryptotephra from Kamchatka in a Greenland ice core and new tephra links between distal climate records from Greenland and the northwest Pacific

First identification of cryptotephra from Kamchatka in a Greenland ice core and new tephra links between distal climate records from Greenland and the northwest Pacific

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