Geology of Ft. Apache Region, Ariz. — Reagan. 271 
f. Limestone 4 
g. unseen ; shale- 25 
h. massive limestone 2 
i. unseen ; shale ? 75 
j. Limestone 2 
k. unseen ; shale ? 50 
Total of 5 32S 
Tonto Formation: 
6. Sandstone: 
a. Brown to red, coarse vitreous, sandstone, mas- 
sive to shaly 100 
b. Gray fine-grained sandstone, weathering red, 
falling apart in angular blocks 75 
c. Shaly calcareous sandstone 57 
d. Vitreous, red, purple and white sandstone.... 150 
e. Coarse siliceous conglomerate 25 
Thickness of 6 425 
Archaean : 
7. Hornblendic rock and schists; unconformable . ... 5 00 
Total Thickness of Section 2360 
Section hi. Section on west bank of Cibicu creek one mile north 
of farmers residence. 
Upper Red Wall Group: feet 
1. Hard white limestone, very fossiliferous, fossils of Spirifer 
family predominating. This limestone is the cap of the first 
mesa bench west of the creek 12 
2. Gray, brown to buff, easily broken, soft limestone (Prodnctus 
cora) 1 
3. Sandstone, brown to buff, shaly 10 
4. Limestone, brown soft, fossiliferous, Lamellibranch fossils 
predominating 6 
Lower Red Wall Group: 
7. Shaly to massive, rough to the feel, dark-gray, calcareous 
sandstone often composed in part of lime particles, and the 
ground up material of. other rocks. This is a mill stone grit 
rock 20 
8. Brown sandstone 8 
9. Red sandstone breaking down +0 red earth 40 
10. Reddish to brown shale 12 
11. Bluish-white, soft limestone in which are Gasteropod and 
Lamellibranch fossils 4 
12. Brown sandstone 6 
13. Black shale 2 
14. Not seen, shale and sandstone? 25 
Total 159 
