GEOLOGY OP THE LUZERNE QUADRANGLE 



n 



Judging by many observed outcrops, practically all the rock of 

 the large area, including Bartlett mountain in the southern part of 

 the quadrangle, consists of rather uniform, typical, medium-grained, 

 moderately foliated, greenish gray quartz-hornblende syenite. 



Table showing approximate volume percentages of minerals in thin 

 sections of fades of the syenite-granite series 





CO 



s 



a 

 1 



3 



t; 

 





 



8 



.£P 

 



d 



t 















■d 

 a 



1 







s 



s 



1 



<u 



■4-* 





(U 



g 



4J 







'S 



4-> 



1 



<u f 



4 



5 



IS 



19 



23 



i6 

 17 



7 

 13 



24 

 2S 



I 

 12 

 20 



8 



9 



10 



26 



4 J4 

 S f I a 

 8 i 12 



piV 

 9C3 



8JS 

 8k2 



5 i 17 

 6i6 



14 h 12 

 14 c 4 



4 C I c 



6 i 12 

 9gSa 



If3 

 I c 2 



2g4 



iSh 7 



40 

 ss 



10 



42 



43 

 SS 



13 



12 



25 



25 



20 



I 



10 

 10 



20 

 II 



20 



45 

 41 



31 

 30 

 40 



35 



27 



35 



37 



22 

 15 

 22 

 20 



30 

 32 



28 



16 

 30 

 39 



25 





8 





2 

 2j 



i 



4 



1 



I 

 14 



i 

 i 



3 



1 

 little 



i 



i 



i 

 1 

 1 



1 

 1 



1 

 i 



i| 



i 

 i 



1 

 li 



1 



little 

 1 



1 



i 

 \ 



\ 



4 



i 



1 



4 

 i 



i 

 i 



little 



little 



\ 









-S 











a 

 2 

 O 



15 



II 



6 



i 



20 

 30 



8 

 9 



4 

 7 

 4 



18 

 12 



2 



3i 

 3 



3i 



I 

 I 



I 



"6 



5 

 I 

 8 

 6 





















Granite 

 por- 

 e phyry 



■■-i 



little 







43 

 30 



47 

 48 



20 

 36 

 39 



5 



7 

 22 



9 

 12 



24 

 25 



littk 



1 









5^ 

 3 



8 













w 



I 

 li 



1 









0) f 







i 







* 



3* 



12 

 10 



4 













2 

 3 



3 



"6 



I 



4l 

 3i 



4i 

 ll 



iittle 

























o \ 



II 





'67 



35 



... 









b [ 

















The area several miles long lying north and northwest of Black 

 Spruce mountain shows many exposures of typical quartz syenite 

 varying to grano-syenite, which, in certain places along the border, 

 may be seen to grade into the surrounding true granite. 



Most of the syenite of the area lying between the Hudson river 

 and Bald mountain is of the rather normal type with some local 

 zones notably quartzose. Along the eastern border its passage into 

 granite is well shown. 



Just west of the river (opposite Ferguson brook) the area of 

 syenite shows many exposures of the very typical quartz syenite. 

 It is excellently exhibited in a ledge recently blasted open by the 

 river road toward the south. No. 24 of the accompanying table 

 shows the minerals observed in a thin section from this ledge. 



In the Stony Creek station area the syenite is darker and more 

 hornblendic than usual, and slightly porphyritic, on all sides of the 

 small mapped mass of gabbro. A few small bands or lenses of the 



