Ice-flow and meltwater landform assemblages in the Gulf of Bothnia
نویسندگان
چکیده
The Gulf of Bothnia is a shallow, elongate basin dividing Sweden and Finland, and is located in the centre of the terrain formerly occupied by the Fennoscandian Ice Sheet (FIS). It is considered to have hosted a variety of different glaci-dynamic environments during the evolution of the FIS, but direct glacial geological or geomorphological evidence from the Gulf itself is almost entirely lacking. Recent acquisition of high-resolution multibeam data enables direct investigation of the basin for the first time. These data reveal a wealth of glacial landforms in the Gulf of Bothnia including glacial lineations, ribbed moraine, eskers, meltwater channels, moraines, crevasse-squeeze ridges and iceberg ploughmarks with a variety of different morphologies. Distinct landform assemblages record multiple ice-flow events or phases of differing glaci-dynamic character. Two contrasting glacial landform assemblages are presented from the western and northern Bothnian Sea.
منابع مشابه
Controls on the early Holocene collapse of the Bothnian Sea Ice Stream 1 2
35 36 New high resolution multibeam data in the Gulf of Bothnia reveal for the first time the 37 subglacial environment of a Bothnian Sea Ice Stream. The geomorphological record suggests 38 that increased meltwater production may have been important in driving rapid retreat of 39 Bothnian Sea ice during deglaciation. Here we apply a well-established one-dimensional 40 flowline model to simulate...
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