192 GEOLOGY OF THE EUKEKA DiSTEICT. 



HAMBURG. 



Feet. 



10. Dark bluish black limestone, carrying Hamburg limestone fossils 800 



7,800 



Divided according to the epochs adopted at Eureka we have : 



Lone Mountain limestone 1, 450 



Eureka quartzite 350 



Pogonip limestone 5, 200 



Hamburg limestone 800 



The Hamburg limestone yielded the following species: 



Protospongia sp.! Conocephalites sp.f 



Lingulepis niinuta. Crepicephalus nitidus. 



Orthis sp.f Crepicephalus unisulcatus. 



Agnostus bidens. Chariocephalus tumifrons. 



Agnostus communis. Illaenurus sp. f 



While at White Pine the relationship between the Cambrian and 

 Silurian is well shown, the Devonian has not been recognized directly over- 

 lying the Lone Mountain Silurian. Between Pogonip Mountain and the 

 next ridge to the eastward a displacement brings up the Nevada limestone, 

 forming the massive beds of Mount Argyle and Treasure Peak. 1 This 

 limestone is here overlain by the black argillaceous shale, which passes 

 into sandstone, followed by Carboniferous limestone. The black shale is 

 the counterpart of the corresponding terrane at Eureka, a comparison of 

 the two sections showing the greatest resemblance. The coarse yellow 

 sandstone above seems to be the equivalent of the Diamond Peak quartz- 

 ite, although here at White Pine it is represented by only a few hundred 

 feet, while the black shale attains a development of 1,000 feet. From the 

 Nevada limestone there has been collected an abundant fauna characteristic 

 of the middle and upper beds. It was for the most part obtained by the 



'U. 8. Geological Exploration of the Fortieth Parallel, vol. 3, Mining Industry, p. 409, and 



accompanying atlas sheet 14. 



