The postglacial retreat of Svalbard glaciers has been interrupted by relatively short-lived readvances controlled by climatic as well as local glacial, meteorological, and geological controls. This complicates the unravelling of the complex glacial history and adequately relating it to the regional deglaciation pattern and climate evolution. Particularly small, fjord-terminating glaciers are more influenced by local factors. Swath bathymetry, sub-bottom acoustic profiling, and two sediment cores were analysed to reconstruct the glacier dynamics, sedimentary processes, and deglaciation history of Recherchebreen in Recherchefjorden, western Spitsbergen, Svalbard. Two distinct overlapping debris-flow lobes and a distinct reflector within the terminal moraine ridge suggest that Recherchebreen reached the location of the terminal moraine at least twice during the Holocene. A radiocarbon age of 2281–2817 cal. a BP recovered from 12 to 13 cm core depth on the crest of the terminal moraine suggests that the first advance of Recherchebreen reached this location prior to the Little Ice Age (LIA) and formed the initial terminal moraine ridge. According to historical maps, the latest advance to reach the terminal moraine occurred during the LIA. Recessional moraines on the fjord floor mark the gradual retreat of Recherchebreen since the LIA, and historical map data show that the general retreat of the glacier has been interrupted by readvances and a surge event in 2018–2020. This study emphasizes the importance of using sedimentological and sub-bottom data in addition to morphological data when studying the age and formation of terminal moraines in Svalbard.
Thaarup et al. (Wed,) studied this question.