Landform interpretation and landscape evolution in Fosdalen, Western Norway
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- Institutt for geografi 
This thesis challenge the hitherto suggested deglaciation chronology in Fosdalen, western Norway. Through observations, lichenometry, and reinterpretation of previously mapped Younger Dryas moraines, the development of several landforms within the complex landscape is investigated. Volume calculations and headwall retreat rates indicate a minimum compound cirque age of 510.000 yr. The Little Ice Age maximum for the respective cirque glaciers is estimated to 1769 and 1854 ± 4 yr. Based on observations, it is suggested that former landform interpretations may be wrong due to equifinality. Hence during the Nor stadial, it is proposed that the Strynedalen valley glacier flowed westward through Fosdalen. Furthermore, a previously mapped Younger Dryas moraine has been reinterpreted as part of a hitherto unmapped debris -landform system, presumably consisting of minimum two rock slope failures deposited onto a cirque glacier during the Vinsrygg stadial. Two identified relict rock glaciers below an active talus system, and ice/debris creep systems on the western cirque glacier foreland, indicate a former permafrost lower limit at 860 m a.s.l. during the Vinsrygg stadial. A lateral moraine at 840 m a.s.l. and a gently sloping subglacial till terrace indicate that the Lodalen valley glacier synchronously flowed into Fosdalen. Finally, a flood plain and change of river course indicate a glacial lake outburst flooding. Combined with the reinterpreted landforms, the probability for the existence of a reconstructed Erdalen Event cirque glacier as suggested by Nesje and Dahl (1992) is impaired.