TY - JOUR
T1 - Holocene tephras highlight complexity of volcanic signals in Greenland ice cores
AU - Coulter, S.E.
AU - Pilcher, J.R.
AU - Plunkett, G.
AU - Baillie, M.
AU - Hall, V.A.
AU - Steffensen, Jørgen Peder
AU - Vinther, Bo Møllesøe
AU - Clausen, Henrik Brink
AU - Johnsen, Sigfus Johann
PY - 2012/11/15
Y1 - 2012/11/15
N2 - Acidity peaks in Greenland ice cores have been used as critical reference horizons for synchronizing ice core records, aiding the construction of a single Greenland Ice Core Chronology (GICC05) for the Holocene. Guided by GICC05, we examined sub-sections of three Greenland cores in the search for tephra from specific eruptions that might facilitate the linkage of ice core records, the dating of prehistoric tephras and the understanding of the eruptions. Here we report the identification of 14 horizons with tephra particles, including 11 that have not previously been reported from the North Atlantic region and that have the potential to be valuable isochrons. The positions of tephras whose major element data are consistent with ash from the Katmai AD 1912 and raefajkull AD 1362 eruptions confirm the annually resolved ice core chronology for the last 700years. We provide a more refined date for the so-called "AD860B" tephra, a widespread isochron found across NW Europe, and present new evidence relating to the 17th century BC Thera/Aniakchak debate that shows N. American eruptions likely contributed to the acid signals at this time. Our Results emphasize the variable spatial and temporal distributions of volcanic products in Greenland ice that call for a more cautious approach in the attribution of acid signals to specific eruptive events.
AB - Acidity peaks in Greenland ice cores have been used as critical reference horizons for synchronizing ice core records, aiding the construction of a single Greenland Ice Core Chronology (GICC05) for the Holocene. Guided by GICC05, we examined sub-sections of three Greenland cores in the search for tephra from specific eruptions that might facilitate the linkage of ice core records, the dating of prehistoric tephras and the understanding of the eruptions. Here we report the identification of 14 horizons with tephra particles, including 11 that have not previously been reported from the North Atlantic region and that have the potential to be valuable isochrons. The positions of tephras whose major element data are consistent with ash from the Katmai AD 1912 and raefajkull AD 1362 eruptions confirm the annually resolved ice core chronology for the last 700years. We provide a more refined date for the so-called "AD860B" tephra, a widespread isochron found across NW Europe, and present new evidence relating to the 17th century BC Thera/Aniakchak debate that shows N. American eruptions likely contributed to the acid signals at this time. Our Results emphasize the variable spatial and temporal distributions of volcanic products in Greenland ice that call for a more cautious approach in the attribution of acid signals to specific eruptive events.
U2 - 10.1029/2012jd017698
DO - 10.1029/2012jd017698
M3 - Journal article
SN - 2169-9003
VL - 117
SP - D21303
JO - Journal of Geophysical Research: Earth Surface
JF - Journal of Geophysical Research: Earth Surface
ER -