| Summary: | Arctic temperatures are rising twice as fast as global temperatures. Consequently, understanding theeffect of this change on glacial dynamics and sea-level variations is of critical importance. The high-Arcticarchipelago of Svalbard is a unique site to study ice marginal landforms and their paleo-environmentalimplications and to link Holocene climate and glacial variations. This study maps and age dates themoraine complex of Nansenbreen, a glacier terminating in the fjord of Isfjorden, in Borebukta north ofErdmannflya lowland. This reconstruction aims to determine the processes of formation of the morainecomplex and its implications for sea-level, glacial activity and Late Holocene climate reconstruction andmodelling. A sedimentological and landform map is therefore produced, using aerial images and fieldobservations. The map is coupled with radiocarbon dating of moraine deposits. Thereby, two moraines are differentiated. The most ice-distal moraine is interpreted as marking themaximum extent of Nansenbreen. Both moraines present features suggesting that they were glaciotectonisedthrough englacial-thrusting during surge events. Radiocarbon dates allow to establish a maximumconstraining age of 750 +/- 50 years BP for the maximum extent of Nansenbreen. This age correspondsto the Medieval Warm Period, an epoch marked by warm climate conditions. Hence, it is thoughtthat Nansenbreen underwent a surge triggered by influxes of warm Atlantic ocean currents into Isfjorden.Finally, the mapping shows that the moraines formed after a regression undergone by the wholeErdmannflya lowland. Erdmannflya therefore represents a suitable study site for sea-level studies. Svalbard Holocene Elucidation of Raised Beach Emergence and Timing (SHERBET)
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