BULL. GEOL. SOC. AM. 



VOL. 13, 1901, PL. 52 



Figure 1.— Chief Mountain, Lewis Range 



Looking east along Chief Mountain ridge. An = Algonkian— Altyn limestone ; Kb = Cretaceous— Benton shah 

 Upper part Chief Mountain shows upper member Altyn formation 



Figure 2. — Cliffs at Northern Base of Chief Mountain 



Looking southeast. Aa = Algonkian — Altyn limestone ; Kb = Cretaceous— Benton shale. Limestone exhibits 

 vertical slickenfaces with horizontal motion and in general chaotic fracture 



CHIEF MOUNTAIN, LEWIS RANGE 



