CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
97 
4. DIKES IN BRECCIA. 
Descriptions, hitherto unpublished, supplied by Arnold Hague and 
T. A. Jaggar, jr. Analyses A, B, I), by II. N. Stokes, record No. 
1804; C, E, F, G, H, by W. F. Hillebrand, Nos. 1765 and 1801. 
A. Hornblende-pyroxene-andesite, Eagle Creek. Contains plagio- 
clase, hornblende, pyroxene, quartz, and apatite. 
B. Leucite-absarokite, Sunlight Valley. Contains phenocrysts of 
olivine and augite, with secondary alteration of the olivine to serpen- 
tine. The groundmass contains magnetite, augite, plagioclase, and 
orthoclase. Leucite abundant. 
C. Gabbro -porphyry, Deer Creek. Contains plagioclase, pyroxene, 
olivine, ilmenite, and apatite. 
D. Hornblende-augite-andesite, Wind River Plateau. Contains 
phenocrysts of augite, hypersthene, and hornblende, plagioclase, and 
fine magnetite grains. 
Si0 2 .. 
ALA- 
Fe 2 3 
FeO.. 
MgO. 
CaO . . 
Na 2 0. 
K 2 0.. 
Ti0 2 
P 2 5 . 
Zr0 2 . 
Cr 2 3 . 
v 2 o 3 . 
NiO.. 
MnO. 
SrO . . 
BaO.. 
Li 2 . 
C0 2 .. 
CI.... 
FeS,.. 
50.72 
16.01 
4.35 
4.20 
7.06 
9.02 
2.92 
1.13 
.40 
2.14 
1.08 
.29 
none 
.07 
.09 
.11 
trace 
.85 
100. 44 
B. 
47.32 
11.22 
2.91 
5.81 
15.96 
7.11 
1.88 
3.79 
.31 
1.71 
.75 
.61 
trace 
trace 
.11 
.05 
.22 
trace 
.13 
99.89 
c. 
1). 
50.29 
15. 85 
s. 22 
1.43 
4.65 
7.71 
2. 98 
3. 53 
1.77 
1.98 
.96 
.51 
trace 
.15 
.09 
.15 
trace 
none 
trace 
100. 2< 
60.15 
17. 85 
2.00 
2.02 
3.26 
5.48 
3. 95 
2.36 
.25 
1.24 
.47 
.22 
none 
.07 
.10 
.20 
none 
none 
99.62 
Bull. 168- 
