LØSMASSE

The superficial deposits occuring within the map-area are described and classified according to their genesis. In the mountains a discontinuous or thin cover of till dominates with peat in the depressions. In the lowland areas glaciomarine sediments were deposited at a sea-level situated c. 155 m above the present one. The deglaciation of this area took place during the Bølling and Allerød chronozones. During the Younger Dryas the glaciers andvanced to the Tautra Moraines, situated some 20 km to the cast of this map-area. This led to an intense calving of the glaciers in the Trondheimsfjord. Drifting icebergs caused a marked increase in the content of coarse-grained rock fragments in the glaciomarine sediments. During the shoreline displacement the sediments below the upper marine limits were influenced by fluvial erosion and slides. Short account are given on the potential for different utilization of the mapped superficial deposits.

The superficial Quaternary deposits occuring within the map-sheet area have been classified and mapped according to their genesis. Fine-grained marine deposits dominates in the main valley below the highest postglacial sea-level. c. 1973 m a.s.l. Numerous glaciofluvially ice-contact deposits are situated in the main valley too, but only the nothernmost was built up to the sea level (true deltas). During the postglacial isostatic uplift, the rivers retransported the glaciofluvial deposits and most of this material was deposited as regression-deltas at lower levels. Above the highest sea level quaternary deposits are almost lacking except for scattered till.
Løsmasse og arealbruk: The utilization and evaluation of the superficial deposits with regards to cultivation, forestry, waste disposal, engineering, groundwater, sand and gravel resources and nature conservation, are discussed. A field trip guide to the area is presented.

The superficial deposits occuring within the map-area are described and classified according to their genesis. In the mountains a discontinuous or thin cover of till dominates with peat in the depressions. In the lowland areas glaciomarine sediments were deposited at a sea-level situated c. 180 m above the present one. In Frosta and Skatval these sediments are overlain by till, deposited by a glacial advance during early Younger Dryas, reaching just to the west of the map-area. Marginal moraines from a late Younger Dryas glacial advance can be traced more or less continuously from Hegra in Stjørdal toowards Hoklingen and Alstahaug. During the shoreline displacement the sediments below the upper marine limit were influenced by fluvial erosion and slides. Short accounts are given on the potential for different utilization of the mapped superficial deposits.

The superficial deposits occurring within the map-area are described and classified according to their genesis. In the mountains till and organic deposits dominate. In the lowland areas glaciofluvial and glaciomarine sediments were deposited at a sea-level situated c. 180 m above the present one. During the shoreline displacement these sediments were strongly influenced by fluvial erosion and slides. The ice recession vas interrupted by a glacial advance during the first half of the Younger Dryas glacial advance ca be traced less continuously from the lakes Store Dragstsjøen - Foldsjøen towards Frigården, Lånke, and Hegra in the Stjørdal valley. Radiocarbon datings from Frosta, Levanger and Verdal indicate that these marginal deposits were formed during late Younger Dryas. Short accounts are given on the potential for different utilization of the superficial deposits.

The superficial deposits occurring within the area covered by the map-sheets are classified genetically and described. Most of the deposits are tills covering wide areas in the southeast, where there are also many deposits of glaciofluvial origin. Fluvial deposits are deposited mainly in the Jakobselva valley, along the Russian border. Along the shore there are few superficial deposits, except for small marine deposits. Brief descriptions are given of the lithology and grain-size distribution of all the superficial deposits. A model for the sequence of geological events during the Quaternary era is proposed based on earlier work and recent field mapping. It is suggested that the deglaciation of the coastal area of Sør-Varanger took place about 12,500 - 10,000 years B.P.

The superficial deposits within the map-sheet Kilebygd, southeastern Norway, are classified and described. Most of the area is dominated by exposed bedrock or a thin and discontinuous cover ot till. In the Nordsjø-Vollsfjorden and Skien basins, below the marine limit(c. 145 m a.s.l), fine-grained marine sediments dominate. A large glacifluvial deposit, Geiteryggen, exists at the eastern end of Nordsjø. Ice movements and the course of deglaciation are constructed. The oldest ice movement was towards SSE, later turning towards SE and ESE. Features associated with glacial events marking small advances or halts of the ice-front during the deglaciation in late Younger Dryas and early Preboreal time have been detected within the map-area. The Geiteryggen frontal deposit with the Ski Moraine in the Oslofjord region and dated to c. 10,000 years B.P. The mapped area was ice-free about 9,850-9,900 years B.P. Short accounts are given on shorelines, shorelevel displacement and pollen analysis. The potential for different utilization of the superficial deposits is also briefly discussed.

The superficial deposits ocurring within the map-sheet area are classified according to their genesis and described. Till is the dominationg sediment, but considerable glacifluvial deposits also occur. Glacier movement directions have been recounstructed in eight phases and subphases. The three youngest subphases correlate with events during the deglaciation. The older phases are considered to span most of Weichselian time. Of the eight glacial events known form the Porsangerfjord area, four occur within the map-area: the Repparfjord event (Older Dryas?), the Gaissa and the Main events (mainly Younger Dryas?) and the Rotnes event (early Preboral?). Extensive deposits, mainly glacifluvial, are related to the Main event. Radiocarbon datings are lacking and suggested ages are based on correlation with dated events in Troms.

The superficial deposits occurring within the map-area are described and classified according to their genesis. In the mountains, till and organic deposits dominate. In the lowland areas glaciofluvial and glaciomarine sediments were deposited at a sea-level situated c. 175 m above the present one. During the shoreline displacement these sediments were strongly influenced by fluvial erosion and slides. The ice recession was interrupted by a glacial advance which took place dUring the first half of the Younger Dryas Chronozone, reaching just to the north of the map-area. Another glacial advance can be traced from the southwestern part of the map towards Reinsfjell and possibly to the western part of the lake Selbusjøen. These marginal moraines were deposited during late Younger Dryas. Short accounts are given on the potential for different utilization of the superficial deposits.

The superficial deposits within the area of map-sheet Reisadalen, 1734 III, in nothern Troms, North Norway, are classified according to their genesis and described. Ice movements and the course of deglaciation are reconstructed. The Reisafjord moraines are correlated with the Tromsø-Lyngen or the Ra moraines of Younger Dryas age. The younger Storbakken, Bergmo and Sappen moraines are of Preboral age, formed 9900-9800 B.P., 9700-9500 B.P. and 9400±250 B.P., respectively. Short accounts are given on shorelines, shore-level displacement and pollen analyses. Till and weathering material cover large areas of the mountainous regions. The bottom of the valley is filled with loose deposits with thicknesses up to 200 m. Large deposits of glaciofluvial and fluvial material represent valuable sand and gravel resources in the area. The potential for different utiliziation of the superficial deposits is also briefly discussed.

The superficial deposits occurring within the area of this map-sheet are classified according to their genesis and described. Based on glacial striae and till stratigraphy 3-4 regional and one (youngest) local icemovement directions are reconstructed. During deglaciation the meltwater was ice-directed. Three phases in the deglaciation are distinguished on the basis of changing meltwater drainage routes.