GEOLOGY OF THE LONG LAKE QUADRANGLE 



525 



This is the most acid of any rock yet analyzed occurring as a part 

 of the general syenite mass and is an unquestionable granite. It is 

 quite close to order 3, and though not quite so acid much resembles 

 the Morris granite in composition, except for the higher lime. For 

 convenience in comparison the four analyses, and that of the 

 Morris granite are here placed side by side. 





I 



II 



III 



IV 



V 



Si02 



61 .02 



17.71 

 2-75 



2-54 



2.01 



3.68 



4.40 

 5-77 



62.85 



16.80 



2 .96 



2.89 



1.48 



3-24 

 4.09 



5-49 

 0. 24 

 0.13 

 0.09 

 0.13 



O.OI 



0.02 



trace 



0.21 



0.06 



68.15 

 16.53 

 1 . 26 

 1 .00 

 0.64 

 2.48 

 4 . 22 

 5-59 



. 10 

 . 02 



0.03 



74.17 

 13-30 



0.26 



0.77 

 0.81 

 2.34 



3-43 

 4-53 



0.02 





A1203 



76.41 



PeaOs 



12 .41 



FeO 



1 .01 



MgO 



0.50 



CaO 



0.46 



Na^O 



0.78 



K2O 



3-34 



H2O+ 



4-33 



H,0— 





0-34 



TiO^ 





0.13 



P2OS 



0.02 



0.03 



F 



trace 



S , 





O.OI 



Zr02 



. 10 



O.OI 



MnO 



0.02 



0.06 



trace 



BaO '. 









Total 



100 .00 



100.69 



100 .02 



99-63 



99.84 





I Syenite, (monzonose) lo-C-i, microscopic analysis. 



II Syenite, (monzonose) 10-B-2, E. W. Morley, analyst. 



III Quartz syenite (toscanose) 869, microscopic analysis. 



IV Granite (toscanose) 10-D-3, microscopic analysis. 



V Morris granite (alaskose) 15-A-3, E. W. Morley, analyst. 

 Grenville igneous rocks. There occurs in frequent association 



with the Grenville sediments of the quadrangle, especially with the 

 quartz gneisses, a rock which is not especially gneissoid, has an 

 igneous look, and also at times appears to show igneous contacts 

 against the quartz schists, though these are so disturbed that it is 

 difficult to be certain in the matter. The texture is fane grained 

 granitic, with abundant glittering feldspar cleavages, and the color 

 is a grayish white, with a smack of a flesh-colored tinge. It is a 

 fairly easy rock to recognize, though difficult to describe with ex- 

 actness. If an igneous rock it is certainly of much greater an- 

 tiquity than the big intrusions, and to class it with the Grenville, 

 with which alone it occurs, seems the obvious course. Its chemical 

 composition is as follows: 



