624 F. F. GROUT GRAPHIC STUDY OF IGNEOUS ROCK SERIES 







•\ 



X 



\ 



M 



\ 



^ 



y. 



E 



M M 



.E° 



-H- 







X A 



30 W 



ptFICItMCICS 



SILICA 



"So 7b 



excesses 



Figure 2. — Eight Series of Rocks plotted for each analyzed Specimen 



Delta for Duluth, Minnesota, lopolith ; E and O for Julianehaab, Greenland, two lopo- 

 liths or batholiths ; X for Isle of Skye, lopolith or stock ; M for Magnet Cove, Arkansas, 

 laccolith ; A for Assynt, Scotland, laccolith ; H for Haliburton and Bancroft, Ontario, 

 batholith ; square for Nordingra sills. Small spots show standard rocks as in figure 1. 



