326 GUNNAR HOPPE 



MAIN FEATURES OF THE WURM GLACIATION 

 IN NORTHERN EUROPE 



The Wiirm glaciation seems to have begun about 70,000 years ago. As a 

 result of investigations of several Globigerina-ooze cores from the Caribbean 

 Sea and the Atlantic Ocean, a temperature minimum of the early Wiirm 

 (Wisconsin) was dated at about 60,000 years ago, while the temperature 

 maximum of the last interglacial occurred 95,000 years ago (Rosholt, 1961). 



The Scandinavian ice sheet began as a glacierization in the highest parts of 

 the mountain chain, the Scandes. Cirque and valley glaciers first coalesced to 

 form transection glaciers in the mountains and piedmont glaciers in the 

 forelands; further enlargement led to the development of glacier caps. 

 Finally the ice caps from different mountainous areas coalesced into a 

 continuously expanding inland ice sheet. This development was followed by 

 continuing movements of the ice divides; in northern Scandinavia, for 

 instance, an ice divide was situated for a long, though undetermined, time 

 far to the east of the Scandes. 



Penck's classical scheme considered the Wiirm to represent a single climatic 

 cycle (1922). This idea has been supported more recently by BUdel (1960), 

 Graul (1952), Weidenbach (1953) and Fink (1961), among others. (The 

 discussion about the Late Pleistocene climate of Europe has been summarized 

 in an excellent way by Wright (1961).) A different scheme of subdivision of 

 the Wiirm was developed by Soergel (1919), based on loess stratigraphy; it 

 presumes a bi- or tripartition. Interstadials have been suggested, one more 

 marked 44,000 to 28,000 years ago ("Gottweig") and another representing a 

 minor warm oscillation 25,000 years ago ("Paudorf") by Gross (1958), 

 Woldstedt (1958), and others; however, "the recognition of a major early 

 Wiirm interstadial should be considered tentative" (Wright, 1961, p. 965). 

 Recently the idea of an interstadial has received support from a series of C^* 

 datings on a marine clay between beds of gravel and sand in the neighbourhood 

 of Gothenburg, southwestern Sweden, i.e. well within the area covered by the 

 last Scandinavian ice sheet. The result of the datings is 26,000 to 30,000 years 

 (Brotzen, 1961). Radiocarbon datings of shells, which occur on raised beaches 

 at 44-47 m but which are believed to originate in the underlying till in 

 Nordaustlandet, Spitsbergen, have given an age of 35,000 to 40,000 years. 

 Since risks for contamination exist, however, this must be regarded as a 

 minimum value. "Thus the ice-free period was in all probability pre-40,000 

 years ago" (Blake, 1961) and it cannot yet be placed in the Pleistocene 

 timetable. It is obvious that the duration and possible division of the Wiirm 

 period must have had a great influence on the extension and thickness of the 

 ice sheet in northern Europe. 



Numerous scientists have tried to evaluate the climatological situation in 

 Europe during the Wiirm "Pleni-Glacial" on the basis of the depression of the 

 snow-line and the distribution of plants, animals, and frost features (Biidel, 



