FORMATIONS AND PHYSICAL HISTORY 



543 



Fig. 459. Map and section showing relations of igneous rock to the Cretaceous 

 formations in tlu- Cra/.y Mountains of Montana. The scrt km is along tlu- liiu- .!/>' 

 of tlu- map. Klv, Livingston formation; <//, diorite; r, granite-. Tin- especial 

 feature of the map is the extraordinary number of dikes radiating from tin- central 

 intrusion, <//. Length of section about 20 miles. (Livingston and Little Belt, 

 Mont., folios, U. S. Geol. Sun'.) 



appear in localities (Alpine region) where marine sedimentation had 

 been in progress earlier in the period, showing that the movements 

 which were to mark the close of the era were making themselves 

 felt. Limestone is the dominant sort of rock in the Upper Greta- 



