Utbredelsesmønstret av løsmateriale og landformer på Svalbard – noen hovedtrekk

Abstract

About 60% of the archipelago of Svalbard (Spitsbergen) is today covered by glaciers. Most glaciers are cold based in the ablation area and warm based in the accumulation area (subpolar glaciers). Ice-free land areas have permafrost with depth varying from 150 to 450 meters. Weathering material is the most common type of superficial deposits in large areas, while till from inland ice is less widespread. Large ice-cored moraines are located in front of recent glaciers. Valleys with a V-shaped cross profile are common, especially in areas with sedimentary rocks. These valleys have a smooth longitudinal profile in contrast to most valleys formed by glaciers. In Svalbard there are only a few lakes, most of them are situated on the strandflat, and they are often dammed by beach ridges. In fact, large areas in Svalbard are almost without glacial landforms, even in places where erratics show that the area has been glaciated. The reason for this is probably that the ice sheets were cold based during glacial epochs. Glacial erosion by inland ice mainly took place in unfrozen areas below sea level.