THE MAXIMUM EXTENT OF PLEISTOCENE GLACIATION 347 



necessary before turning to Baffin Island where conditions are similar to 

 those of northeastern Labrador-Ungava. Matthews has collected marine 

 molluscs up to an altitude of 120 m above present sea level in the Deception 

 Bay vicinity, south Hudson Strait (Matthews, pers. comm. 1961). Deception 

 Bay lies nearly 600 km from the open Atlantic Ocean and the local marine 

 limit is approximately 150 m above sea level. Marine molluscs collected from 

 the 86 m level by Matthews have yielded a radiocarbon age of 10,450 ±250 

 years. (Geographical Branch No. J.D.I.-61-S6; Isotopes inc. No. 1-488.) 

 This implies that at the time of the Vaiders Readvance in the south, this sector 

 of Hudson Strait was not only open to the Late-Glacial marine incursion, 

 but that it had been inundated for a sufficient interval of time to allow a 

 maximum of some 60 m of relative vertical isostatic recovery prior to 10,450 

 years ago. If this single date can be substantiated, the implications are most 

 important. Assuming that the radiocarbon age of 18.000 years B.P. is accurate 

 for the maximum of the Classical Wisconsin Glaciation in southern Canada 

 and northeastern United States, it seems possible that contemporary conditions 

 in Hudson Strait were characterized by partial, or total absence of glacier ice. 

 This possibility has a most important bearing on the dating and significance 

 of the Sagiek moraine system. At least it can be said that the Saglek moraines 

 are more than 10.500 years old and the implication is that large areas along 

 the Labrador coast, northwards of Nain. remained ice-free at the Classical 

 Wisconsin maximum. Thus it seems probable that the areas occupied by 

 mature detritus, and possibly even that occupied by incipient detritus, were 

 not ice-covered at the Classical Wisconsin maximum. This would corroborate 

 conclusions drawn by Dahl in Norway (Dahl, 1961), and concurs with 

 Andrews" interpretation of the significance of the Saglek and Koroksoak 

 levels (Andrews, 1961). By comparing the enormous difference in glacial 

 conditions between an ice stand at the Saglek moraines or the Koroksoak trim 

 line, and one that overtopped the highest summits, as during the Torngat 

 Glaciation, it seems probable that the Torngat Glaciation is pre-Sangamon 

 in age. If this hypothesis can be substantiated it would provide for a consider- 

 able period of time for the development of mature mountain-top detritus. 



Admittedly, the preceding hypothetical discussion leans too heavily upon 

 two isolated radiocarbon dates and extensive subjective interpretation and 

 extrapolation. The argument, therefore, is tentative and is intended as a 

 suggestion for a future line of inquiry rather than as a positive conclusion. 



CORRELATIONS WITH BAFFIN ISLAND 



Little information is available for Baffin Island, but some significant 

 statements can be made. According to that acute observor, Dr. A. P. Low, 

 the glaciers of northern Baffin and Bylot islands were probably never much 

 more extensive than they are today (Low, 1906, pp. 233-236), Falconer has 

 substantiated this conclusion with the proviso that it must be strictly applied 



