[{"name":"larsson-2021-fosen-vedde-1","title":"Stratigraphy and geochemistry of the Fosen Tephra and the Vedde Ash at three sites on the Fosen peninsula, central Norway","summary":"This dataset contains results from extractions of distal tephra (far-travelled volcanic ash) and from major-element geochemistry analyses of what was identified as two previously known tephras, the Fosen Tephra and the Vedde Ash, from three sampling sites on the Fosen peninsula in central Norway \u2014 the Lomtj\u00f8nnmyran fen, the Dam\u00e5smyran bog, and lake R\u00f8rtj\u00f8nna.\r\n\r\nThe Vedde Ash (c. 12,000 years old; 12 ka) is a well-used tephra isochron in chronological and palaeoclimatological studies of the Last Glacial-Interglacial Transition and commonly marks the Younger Dryas stadial (Greenland Stadial 1) in the accumulations wherein it is identified. The more recently discovered Fosen Tephra (c. 10.2 ka) in turn marks the early Holocene, and thus is useful to confirm the timing of the transition into the warmer climate of this epoch.\r\n\r\nThe sample material was collected in the field in May 2017 in the form of sediment cores by use of Russian corers. Tephra extractions were performed during the fall of 2017 and spring of 2018. Tephra shard concentration estimates were calculated for the Lomtj\u00f8nnmyran and Dam\u00e5smyran sites by comparing tephra counts with counts of Lycopodium spores from added tablets of known spore amounts. Geochemical analyses were performed in April and December 2018.","citations":"Dugmore AJ, Larsen G, Newton AJ (1995) Seven tephra isochrones in Scotland. The Holocene 5:257\u2060\u200a\u2013\u200a\u2060266. doi:10.1177\/095968369500500301\r\n\r\nHayward C (2012) High spatial resolution electron probe microanalysis of tephras and melt inclusions without beam-induced chemical modification. The Holocene 22:119\u2060\u200a\u2013\u200a\u2060125. doi:10.1177\/0959683611409777\r\n\r\nH\u00f8gaas F, Larsson SA, Klug M, Olsen L, Wasteg\u00e5rd S (2021) Palaeolake sediment records reveal a mid- to late Younger Dryas ice sheet maximum in Mid-Norway. Manuscript in preparation\r\n\r\nJowsey PC (1966) An improved peat sampler. New Phytologist 65:245\u2060\u200a\u2013\u200a\u2060248. doi:10.1111\/j.1469-8137.1966.tb06356.x\r\n\r\nLind EM, Wasteg\u00e5rd S, Larsen JJ (2013) A Late Younger Dryas\u2013Early Holocene tephrostratigraphy for Fosen, Central Norway. Journal of Quaternary Science 28:803\u2060\u200a\u2013\u200a\u2060811. doi:10.1002\/jqs.2676\r\n\r\nMangerud J, Lie SE, Furnes H, Kristiansen IL, L\u00f8mo L (1984) A Younger Dryas Ash Bed in Western Norway, and Its Possible Correlations with Tephra in Cores from the Norwegian Sea and the North Atlantic. Quaternary Research 21:85\u2060\u200a\u2013\u200a\u2060104. doi:10.1016\/0033-5894(84)90092-9\r\n\r\nTurney CSM (1998) Extraction of rhyolitic component of Vedde microtephra from minerogenic lake sediments. Journal of Paleolimnology 19:199\u2060\u200a\u2013\u200a\u2060206. doi:10.1023\/A:1007926322026","comments":"The research for which this dataset was created was carried out by Simon A. Larsson under the supervision of Stefan Wasteg\u00e5rd in the years 2017\u2060\u200a\u2013\u200a\u20602021 and contributed to a new interpretation of the timing of the deglaciation on the Fosen peninsula during the Younger Dryas (H\u00f8gaas et al. 2021, in prep.).\r\n\r\nThe collection of the sample material and the analyses performed for the production of this dataset was done with the aid of Fredrik H\u00f8gaas, Helene Sunmark, and Chris Hayward.\r\n\r\nPlease, cite the appropriate articles when using this dataset.\r\n\r\n###### Tephras analysed\r\n* Fosen Tephra (Lind et al. 2013)\r\n* Vedde Ash (Mangerud et al. 1984)\r\n\r\n###### Site locations\r\n* Lomtj\u00f8nnmyran fen (63\u00b0 40\u2019 17.7\u201d N, 10\u00b0 32\u2019 49.5\u201d E)\r\n* Dam\u00e5smyran bog (63\u00b0 47\u2019 59.2\u201d N, 10\u00b0 48\u2019 32.3\u201d E)\r\n* Lake R\u00f8rtj\u00f8nna (63\u00b0 39\u2019 33\u201d N, 10\u00b0 32\u2019 02\u201d E)\r\n\r\n###### Sampling and measurement methods\r\nThe sample material for this research was collected in the form of sediment cores by use of Russian corers (Jowsey 1966). Tephra extractions were performed following slightly modified methods of Turney (1998) for initial extractions and Dugmore et al. (1995) for extractions for geochemical analysis. Tephra shard concentration estimates were calculated for the Lomtj\u00f8nnmyran and Dam\u00e5smyran sites by comparing tephra counts with counts of Lycopodium spores from added tablets of known spore amounts. Geochemical analyses were performed using a Cameca SX100 electron probe microanalyser (a.k.a. EPMA) at the University of Edinburgh, Scotland (Hayward 2012). Glass standards Lipari and BCR-2G were used for control and calibration during the analysis sessions.","category":"Terrestrial","subcategory":"Sediment cores","keywords":"Tephra; Tephrostratigraphy; Major-element geochemistry; EPMA; Fosen; Vedde; Norway","scientist":"Simon A. Larsson","firstname":"Simon","lastname":"Larsson","address":"Department of Physical Geography; Stockholm University","postalcode":"SE-10691","city":"Stockholm","province":"","country":"Sweden","parameters":"Earth science > Paleoclimate > Land records > Volcanic deposits","location":"Continent > Europe > Northern Europe > Scandinavia > Norway","progress":"Completed","language":"English","project":"This research was carried out within the \"Precise linking of late Quaternary palaeoclimate records in the North Atlantic region\" project, funded by Vetenskapsr\u00e5det (The Swedish Research Council, grant number 2015-05255 awarded to Stefan Wasteg\u00e5rd).","publisher":"Bolin Centre Database","version":"1","constrains":"","access":"Free"}]