APPENDIX. 



Section in Central Montana — Continued. 



569 



Names of Formations. 



Thickness 

 in Feet. 



Characteristics. 



_ I W 



f Gallatin lime- 

 I stone. 

 I Flathead quartz- 

 [ ite. 



CD 



m 



1 



— Unconformity -~~- 



Spokane shale. 



Greyson shales. 



Newland lime- 

 stone. 



Chamberlain 

 shale. 



1300 



210 

 950 

 560 



2080 



3. Massive and thin-bedded limestone. 



2. Dark-green and purple micaceous shale, with 

 interbedded limestone and limestone con- 

 glomerate. 



1 . Pink quartzite and sandstone. 



4. Red. 



3. Lustrous gray sericitic shale and slate. 



2. Dense, dark-colored, bluish gray, impure, 



with interbedded slate. 

 1. Slate, and compact, indurated, dark-gray 



shale. 



Neihart quartzite. 

 — Unconformity — 



700 



Massive-bedded. 



Banded gneiss and mica schist, with intrusive 

 porphyries, diorite, and syenite. 



Paleozoic and Mesozoic strata folded, faulted, and cut by igneous rocks, 

 tiary beds nearly horizontal. 



Ter- 



