| Summary: | During the last decade, general Quaternary geological mapping in Nordland county, northern Norway, has provided field-data, supported by radiocarbondating, which have been used as a basis for reconstructing the palaeoclimaticand glacial history for the interval 40-10 ka BP. Much of the lateglacial (13-10 ka BP) history was known from previous investigations, but the new results necessitate significant modifications in som areas. These include bothice extensions, mainly during the younger Dryas Chron, and glacial conditions, as well as timing of events. Radiocarbon dating of shells from sediments underlying and overlying till from the previously described ice phase, theVassdal event, also referred to as Substage A which is represented by the Vega Moraine farter south, indicates that this ice advance represents the Older Dryas ice advance northwest of Svartisen, central Nordland at c. 12.2 ka BP. Earlier knowledge of the glacial variations and palaeoclimate during the lateclacial maximum (30-13), and the Middle Weichselian intervals before that, was very modest for the central and southern parts of Nordland county. The new data suggest that there were significant glacial and palaeoclimatic variations during most of the interval 40-13 ka BP. Occurences of shells of the marine mollusc Arctica islandica, e.g., on the island of Åmøya, indicate that temperate Atlantic water reached the coast of Norway at least as far north as 66 degrees 47' latitude at c.32-38 ka BP. Similar occurences of shells with an age of c.41-42 ka BP are reported from sites farther north, e.g. at 67 degrees 20'N, 68 degrees 48'N and 69 degrees 42'N. The associated temperate sea-surface conditions occurred contemporaneously with fern growing in the inland area at Hattfjelldal, southern Nordland. Major ice advances occurred three times separated by significant ice-retreat phases in the area northwest of theSvartisen glacier betwwn 30 and 13 ka BP. 50688
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