330 



EARTH FEATURES AND THEIR MEANING 



Scale 



FIG. 359. Outline map of the 

 early Lake Maumee, with the 

 bordering moraine and the 

 water-laid moraine remaining 

 on the site of the former ice cliff. 



Within each of the Great 

 peared at that end of the 



Within all areas of small relief, such as 

 the prairie country surrounding the 

 present Laurentian lakes, the earlier 

 and smaller stages of such ice-blocked 

 lakes are generally crescentic in out- 

 line. This is because a moraine in 

 most cases forms the land margin of 

 the lake, and because the ice cliff 

 upon the opposite border, although 

 somewhat straightened, as a conse- 

 quence of wave-cutting and iceberg 

 formation, still retains the convex 

 outlines characteristic of ice lobes 

 (Fig. 359). 



Lake basins a crescentic lake early ap- 

 depression which was first uncovered 



** 



FIG. 360. 



Map to show the first stages of the ice-dammed lakes within the 

 St. Lawrence basin (after Leverett and Taylor). 



