GEOLOGY OF THE TORONTO REGION" 



up shale, limestone and Archaean rocks. These rich 

 but somewhat heavy soils make the basis of the agri- 

 culture of southern Ontario, which is still the most 

 productive province of Canada. The old lake bot- 

 toms of Iroquois and Algonquin origin afford also 

 a great variety of soils of a somewhat different kind, 

 mostly derived from the glacial deposits of their 

 shores either by the action of waves or of rivers 

 entering and forming deltas. Where the waves have 

 eaten into promontories of boulder clay the enclosed 

 boulders are sometimes left in the fields in hopeless 

 numbers, but usually the lake-formed soils are free 

 from stones. They range from the gravels of ancient 

 bars, where the soil is thin and too well drained, 

 into sandy slopes of very light soil, which merge 

 lower down into sandy loam, and finally in the flatter 

 parts form wide stretches of rich silty alluvium. 

 The soils due to lake action have proved themselves 

 excellently adapted for fruit growing, especially the 

 sandy loams, so that the band of Iroquois deposits 

 round Lake Ontario is largely covered with orchards 

 and vineyards. There is probably no part of North 

 America more favorable to mixed farming and fruit 

 growing than the part of Ontario south of the 

 Archaean region. 



GEOLOGICAL EXCURSIONS NEAR 

 TORONTO. 



A number of excursions have been planned for 

 members of the Geological Congress in and near 

 79 



