Quaternary tephrachronology on the Iceland Plateau,north of Iceland

Four major ash zones recorded in piston cores raised from the Iceland Plateau north of Iceland are shown to be coincident with the last four interglacial isotopic stages. Their geochemical composition links the ashes to volcanic events on Iceland. The occurrence of these ash layers, which record events orders of magnitude larger than the ‘normal’ Holocene volcanic eruptions, can not be explained by changes in sea ice cover and atmospheric circulation alone. It is suggested that these events are related to pressure releases in the magma chambers resulting from major deglaciations of the Icelandic Ice Cap.