GENESE

The superficial deposits occurring within the map-sheet are described and classified according to their genesis. Short accounts are also given on sand and gravel resources and groundwater resources. Ablation till and sandy basal till are the dominant deposits. The till cover is mostly continous and thick. The biggest glaciofluvial and fluvial deposits are situated at the mouths of the main valleys. There are also concentrations of these sorted, sandy and gravelly deposits along the main meltwater drainage routes at Hunder in Gudbrandsdalen, and south of Sjusjøen. A fine-grained bluish grey basal till, named the Jørstad till, dominates at 2 m and more below surface througout the area, but mainly in the valleys. The ice flow direction during the initial part of the last glaciation followed the main valleys.
Subsequently the ice movements were directed to the SE. In the next phase the
ice movement were to the SSE-S and locally to the SSW. During the course of
deglaciation the ice movements gradually turned towards lake Mjøsa both
from the west and from the north. The last local ice movements followed the
main valleys. There are indications of a water level at about 180 m a.s.l.
near Lillehammer and at Vingrom 6 km south of Lillehammer. The water level
in lake Mjøsa at Lillehammer sank below 130 m a.s.l. prior to 8.200 years B.P.

This report presents maps of sedimentary environments and seabed sediments (genesis) in the Nordland VI management area off northern Norway. The maps, which cover about 25 000 km² and water depths from 60 m to 2700 m, are based on multibeam echosounder data (bathymetry and backscatter), 215 video lines each 700 m long, seabed sediment samples from 40 stations (grab, boxcore and multicore) and 5500 km of sub-bottom profiler data. The sedimentary environment map has 6 classes, focussing on present depositional environments (erosion and deposition). Large parts of the Nordland VI continental shelf are dominated by erosion processes, but some deposition occurs in topographic depressions and glacial troughs like Trænadjupet and Vesterdjupet. Hemipelagic sediments are deposited in deep water areas on the continental slope and abyssal plain. The seabed sediments (genesis) map comprises a geological interpretation of the uppermost few metres of the seabed, and has 10 classes. On the continental shelf, we find marine suspension deposits, bedload (traction) deposits, bioclastic sediments, till and bedrock with thin or discontinuous sediment cover. The continental slope is dominated by mass movement deposits and a major contourite deposit with the following classes: contourite, debris flow deposit, mass movement deposits and hemipelagic sediments, mass movement deposit (locally covered by younger sediments), debris flow deposits and laminated sediments (>1m) underlain by debris flow deposits.