Lichenometric dating and tephrochronology of sandur deposits, Solheimajokull area, southern Iceland.

Abstract

A series of proglacial sandur deposits infront of Solheimajokull has been dated using a combination of morphological, lichenometric, tephrochronologic and historical evidence. The dates predicted from the lichen sizes for the period of outwash formation and/or abandonment for this period conform closely to the morphologic and historical evidence, with deposits formed particularly in about 1840, 1883, 1935 and 1969. Tephrochronologic evidence from soil sections on the sandar and within the lateral moraine sequence, indicate dates of accumulation associated with glacier expansion at some time between c.600 AD (Skogasandur) and c.1400 AD (Solheimasandur): the lichenometric data cannot be used to date deposits older than about 140 years in age. -from Authors