CLABKE.] 
IGNEOUS AND CRYSTALLINE EOCKS. 
229 
O. Andesite-oligoclase-scapolite-biotite rock, Skwcntna River, 15 
miles above its mouth. Dike. Essential constituents andesine-oligo- 
clase, scapolite, and biotite, with accessory apatite and zircon. 
P. Augite-belugite, Skwentna River, near Hayes River. Dike. Con- 
tains essential feldspar, intermediate between andesine and labradorite, 
augite, and some hornblende. Also a considerable amount of pyrite. 
Q. Tordrillite, Tordrillo Mountains. Dike. Contains phenocrysts 
of quartz, orthoclase, anorthoclase, and anorthoclase-albite, Ground- 
mass consists of quartz and orthoclase. No dark minerals except very 
small quantities of secondary hornblende. 
R. Augite-aleutite, near Kalinai Pass, Aleutian Peninsula. Lava. 
Chiefly labradorite, tending toward andesine, with a considerable 
amount of pale-green augite. 
S. Tonalite-aplite, Yukon River, above Fort Hamlin. Dike. Con- 
sists essentially of quartz and soda-lime feldspars. 
Si0 2 _. 
AL0 3 . 
Fe 2 3 
FeO.. 
MgO. 
CaO.. 
K 2 
H 2 0at 110°.... 
H 2 above 110° 
Ti0 2 
P 2 5 
MnO 
BaO 
SrO 
Li 2 
C0 2 
s(«) 
CI 
62.78 
17.16 
1.96 
2.31 
2.32 
4.84 
4.11 
2.15 
.24 
.88 
.56 
.15 
.06 
.04 
trace 
trace 
none 
.02 
trace 
99.58 
50.23 
19.46 
4.21 
4.20 
3.59 
10.39 
3.08 
1.32 
.16 
1.01 
1.30 
.41 
.07 
.04 
trace 
trace 
.25 
.02 
Q. 
75.84 
13.38 
1.45 
.10 
.07 
3.33 
4.73 
.18 
.n 
.09 
trace 
trace 
trace 
trace 
trace 
none 
k. 
99.74 
99. 88 
56.03 
18.31 
3.47 
4.42 
3.64 
7.43 
3.60 
1.18 
.12 
.31 
1.24 
.13 
.11 
trace 
trace 
trace 
none 
trace 
74.79 
12.59 
1.19 
.31 
3.58 
5.10 
.21 
.09 
1.03 
.17 
trace- 
trace 
none 
none 
none 
.58 
99.99 
99.64 
a Whether S or S0 3 was not determined. 
