IGNEOUS AND CRYSTALLINE ROCKS. 
129 
G. Basalt?, Bear Creek. Lamarose. Resembles A, but with a 
more crystalline groundmass. Contains plagioclase, possibly sani- 
dine, augite, olivine, and iron oxides. Analysis by Chatard, record 
No. 1154. P. R. C. 967. 
H. Lamprophyre, between South Boulder and Antelope creeks. 
Kentallenose. Contains porphyritic augite and olivine in a feldspathic 
groundmass, with apatite, augite, grains of iron oxide, and shreds of 
brown mica. Sp. gr., 2.96. Analysis by Eakins, record No. 1266. 
P. R. C. 966. 
I. Lampropi^re, hills east of South Boulder Creek. Near 
Uuvergnose. Nodules from a decomposed mass. Shows sanidine, 
plagioclase, brown mica, and altered olivine. 
Si0 2 
A1A 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 OatllO°... 
H 2 above 110 c 
Ti0 2 
PA 
Cr 2 3 
NiO 
MnO 
BaO 
4!). 13 
9.05 
3.57 
5.05 
17. 21 
5.68 
2.01 
2.24 
.84 
3.50 
.42 
.38 
.39 
trace 
.15 
. 05 
99.67 
50. 82 
11.44 
.25 
8.94 
14.01 
8.14 
1.79 
3.45 
.58 
.59 
.20 
. 03 
trace 
.19 
.06 
100. 49 
50.03 
14.08 
2.92 
6.11 
10.73 
7.46 
1.46 
2.64 
3.70 
.-61 
.42 
trace 
trace 
.08 
.04 
100. 28 
Bull. 228—04- 
