The weathering of volcanic tephra and how they impact histosol development. An example from South East Iceland

Little is known about the impact of tephra deposits from explosive volcanic eruptions on soil formation and weathering processes in organic soils. The weathering of tephra of basaltic and rhyolitic origin and their impact on Icelandic histosols were studied through a combination of physical, chemical and mineralogical analyses. Two sampling sites were selected according to the presence of the light coloured rhyolitic tephra from the Öræfajökull eruption in 1362 CE and a dark-coloured basaltic Veiðivötn tephra from 1477 CE in the volcanically active area south of Vatnajökull in South East Iceland.