GLACIAL LAKE ALGONQUIN. 



439 



On the Canadian side the continuation of the main moraine of the Port Huron system 

 turns northeast 7 or 8 miles north-northwest of Clinton and the next moraine takes a parallel 

 course northeast from Goderich. The latter moraine appears to be the precise equivalent of the 

 Bay City moraine in Michigan. Following this, five light moraines set close together run 

 northeast from the brow of the Algonquin cliff between Clark and Douglas points, the first 

 one terminating a little south of Clark Point. These are slender ridges, and at present are known 

 only as fragments near the shore. Their courses inland have not yet been worked out, but the 

 characters mentioned suggest that they are deployed ridges of a single moraine, and their places 

 in the series suggest that taken together they may be equivalents of the Tawas moraine in 

 Michigan. Next comes a strong moraine that begins near the shore about 8 miles south of 



Figure 8.— Map showing isobases of Lake Algonquin at its highest stage and isobases of Lake Iroquois as represented by Goldthwait. The numbers 

 above the isobases are altitudes above the horizontal or unaffected part of the beach south of the hinge line; the numbers in parentheses below 

 the isobases are altitudes above sea level. 



Port Elgin and runs northeast to Hepworth, where it turns back to the southeast around the 

 head of the Owen Sound embayment. It passes close east of Port Elgin and may be called 

 the Port Elgin moraine. If the five light ridges south of this moraine are equivalents of the 

 Tawas moraine, then this one may be regarded, at least tentatively, as the equivalent of the 

 Cheboygan moraine hi Michigan. From the relations of several morainic fragments observed 

 by the writer, it seems probable that at this halt the ice front extended eastward along the 

 base of the high escarpment between Owen Sound and Collingwood and only a little above the 

 Algonquin beach, and that after swinging east and north across the Nottawasaga and Severn 

 valleys, it made a deep northward reentrant toward the highlands of Algonquin Park, return- 

 ing south and southwest along the northern margin of the lobe that projected into the basin of 

 Lake Ontario. 



