GEOLOGY OF THE TORONTO REGION 



sheets during the Glacial Period. The palaeontol- 

 ogist will find a variety of Ordovician, Silurian a: 1 

 Devonian fossils in the bed rocks of the region, the 

 Pleistocene geologist may study a complex and impor- 

 tant series of later deposits, the physiographer will 

 observe a more interesting set of surface phenomena 

 than could have been expected in a district without 

 mountains, and the dynamic geologist may study the 

 effects of glacier ice, of rivers, waterfalls and waves, 

 and also see the evidences of important changes of 

 level within post-glacial ages. 



Within one hundred miles of Toronto the follow- 

 ing geological formations are displayed : 



Recent Shore cliffs and wave-built bars. 



Pleistocene . . Glacial, Interglacial and Post-glacial 



beds. 

 Devonian Onondaga and Hamilton 



beds. 



Silurian Cataract, Medina, Clinton, 

 Niagara and Guelph 

 Palaeozoic . A beds. 



Ordovician Trenton limestone, Utica 

 and Collingwood shale, 

 Lorraine shale and 

 Queenston shale. 



Granites, gneisses, greenstones and 

 greenschists. 



The vast interval between the lower part of the 

 and the Palaeozoic is unfilled, and the 

 53 



aean 



i* 



Archaean 



