Vol. 6] Merriam: Virgin Valley and Thousand Creek 



53 



With reference to the age or correlation of the formations 

 included in this list, the following opinions have been expressed : 



f Merriam. 1 * 1907. Miocene ; vipper beds not older 



J than Mascall Beds of John Day region; lower 



beds Miocene, but may represent a different 

 Virgin Valley Beds j phage 



| Gidley.15 1908. Middle or lower Miocene; not 

 [ newer, and may be older than Mascall Beds. 



Pueblo Bange Series 



Blake.i" 1875. Early Miocene. 



Merriam. 1 " 1907. Canon Bhyolite of Virgin 

 Valley superficially resembles a part of the 

 Clarno Eocene series of the John Day region. 



Waring. is 1909. The lava series forming a 

 large part of Steens Mountain is correlated by 

 Waring with the Columbia Biver basalt (Mio- 

 cene). The Steens Mountain lavas are presum- 

 ably the same as the Pueblo Bange Series. 



i* Op. cit., p. 382. 1907. 



is Op. cit., p. 242. 1908. 



i« Op. cit., p. 212. 1875. 



" Op. cit., p. 381. 1907. 



is Op. cit., p. 21. 1909. 



