摘要:

ABSTRACTLandforms in Skåne have been analysed on the basis of two computer-made relief maps in 1:250 000. The relief is represented by hill shading. These maps give both an overview and a detailed view of the landforms. Information about the geology and bedrock topography under the Quaternary cover have also been taken into consideration in the interpretation. This analysis has resulted in three maps, one of the forms in the bedrock, another of the depositional forms in the Quaternary cover, and a third one of glacial spillways and other erosional valleys. Although Skåne is one of the most widely investigated parts of Sweden, several new discoveries were made. These include observations on the existence and extension of minor horsts, the pattern of Late Glacial spillways, the unexpectedly large number of drumlins, the pattern of small moraine ridges, and the distinct delimitation and areal extent of the hummocky moraine in the south (Backlandet).The information gained has been used for an analysis of the processes that led to the present landforms and of the timing of landforming events. Skåne has a varied bedrock due to its position within the Tornquist Tectonic Zone. Late Cretaceous inversion tectonics was succeeded by erosion on obliquely elevated bedrock blocks. There are two erosional levels in the raised areas at about 150 and 100 m a.s.l. The relief is interpreted to have been produced by erosion to successively lower base levels, including exhumation of sub-Mesozoic relief. The bedrock knolls of this relief, produced by Mesozoic etching and subsequent stripping, are now often cores in the drumlins, as also are the Jurassic volcanic necks. The present valley systems are almost all found to be influenced by the Late Glacial drainage and several water gaps occur. This focuses the attention to the relative importance of preglacial and glaciofluvial processes in the formation of the valleys.The deglaciation of the area was reconstructed with the aid of the Late Glacial erosional and depositional forms and the Quaternary lithostratigraphy. Two phases of the Late Weichselian deglaciation have been reconstructed: 1) The main recession during which a large body of ice stagnated in the south and was surrounded by diverging ice streams, and large glacial lakes were formed in the Vomb Basin; 2) The Low Baltic readvance with a renewed damming of a glacial lake in the Vomb Basin. During the recession of the ice several systems of glacial spillways formed or reshaped the valleys of Skåne.

ISSN:0435-3676    

DOI:10.1080/04353676.1991.11880333

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

ABSTRACTBetween 1982–1990, on the slopes of Tarfala valley above timberline, at an altitude 1140–1220 m a.s.l, soil movement was mesured by means of wooden pegs (columns) inserted in the soil. Three types of soil movement were distinguished: two were dominant slope processes (frost creep and gelifluction) and one was a dominant vertical movement. The two first movements are illustrated by curves in peg profiles which were either concave downslope (frost creep) or convex downslope (gelifluction). Frost creep is a movement of soil particles and also of soil layers reflecting the structures of segregated ice. It depends on conditions of zonal climate but chiefly on local factors, especially on soil moisture (the influence of permafrost, seasonally frozen layers and snow fields) as well as on the inclination of the slope surface.

ISSN:0435-3676    

DOI:10.1080/04353676.1991.11880334

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

ABSTRACTVarious morphological features in the mountain ranges of the Dry Valleys region have been interpreted as reflecting late Tertiary overriding by an expanded East Antarctic Ice Sheet. Such features include large-scale stoss and lee topography, and anastomosing systems of channels and potholes. Alternative explanations for the features have been suggested and throw some doubt on the overriding hypothesis. This paper investigates channels and potholes in part of the Asgard Range in some detail and concludes that they do indeed reflect overriding ice. The channels are subglacial meltwater systems reflecting ice flow across the mountains from southwest to northeast. The channels were probably cut by sudden outbursts of meltwater beneath a local warm-based zone within a predominantly cold-based ice sheet.

ISSN:0435-3676    

DOI:10.1080/04353676.1991.11880335

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0435-3676    

DOI:10.1080/04353676.1991.11880336

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor