CLAKKK.) 
IGNEOUS AND CRYSTALLINE ROCKS. 
135 
8. BEARPAW MOUNTAINS. 
Described by Weed and Pirsson, Amer. Journ. Sci., 4th series, vol. 
1, pp. 283 and 351, and vol. 2, pp. 136 and 188. Analyses by H. N. 
Stokes, record Nos. 1558 and 1572. 
A. Quartz-syenite-porphyry, Gray Butte. Contains anorthoclase, 
microlites of plagioclase, segirite, augite, quartz, and apatite, with an 
occasional zircon and very few biotite leaves. P. R. C. , 897. 
B. Quartz-syenite, Beaver Creek stock. Contains orthoclase, albite, 
quartz, augite, and iron oxides, with very little biotite, hornblende, 
andsphene. P. R. C, 900. 
C. Basic syenite or rnonzonite (yogoite), Beaver Creek. Contains 
orthoclase, plagioclase, diopside, biotite, iron oxides, and apatite. 
P. R. C, 902. 
Si0 2 
A1A 
Fe 2 3 
FeO 
MgO 
cao :. 
Na 2 
K 2 
H 2 at 110° 
H 2 above 110° 
Ti0 2 
PA 
MnO 
SrO 
BaO 
Li 2 
S0 3 
CI 
F 
66.22 
16.22 
1.98 
.16 
.77 
1.32 
6.49 
5.76 
.08 
.24 
.22 
.10 
trace 
.06 
.29 
trace 
.02 
.04 
trace 
99.97 
B. 
68.34 
15.32 
1.90 
.84 
.54 
.92 
5.45 
5.62 
.15 
.30 
.21 
.13 
.07 
.04 
.08 
none 
trace 
.04 
none? 
99. 95 
52.81 
15.66 
3.06 
4.76 
4.99 
7.57 
3.60 
4.84 
.16 
.93 
.71 
.75 
trace 
.09 
.24 
trace 
trace 
.07 
trace 
100. 24 
