176 



University of California Publications. [Geology 



Stream terraces are found along the John Day and its main 

 branches, and there are many old alluvial slopes covered with 

 angular rubble. Remains of Elcphas and Equus are preserved 

 in the Quaternary terrace gravels. 



HISTORY OP CORRELATION. 



The earliest expression of opinion regarding the correlation 

 of the Tertiary formations in the John Day valley seems to have 

 been that of 0. C. Marsh 9 in 1875. Of the John Day Marsh 

 wrote: "The typical localities of this Miocene basin are along 

 the John Day River, and this name may very properly be used 



to designate the lake basin The upper beds alone of this 



series correspond to the deposits in the White River basin. The 

 lower portion also is clearly Miocene, as shown by its vertebrate 

 fauna, which differs in many respects from that above." The 

 Clarno is referred to as "the Eocene beds containing fossil 

 plants." The presence of Pliocene beds above the Miocene is 

 also noted. The so-called Pliocene is evidently the Mascall and 

 Rattlesnake, near the typical exposures of which on Cottonwood 

 Creek Marsh is known to have camped. 



Views similar to those of Marsh were entertained by Cope 10 

 who wrote of "the White River beds of the John Day region". 

 In the same paper the Mascall and Rattlesnake are referred 'to 

 as "the Loup Fork formation of Cottonwood Creek". 



By Clarence King 11 the John Day was correlated with the 

 Truckee group, and both formations were supposed to have 

 been deposited in the same body of water, Pah-Ute Lake, in 

 explanation of this correlation King stated that : ' ' The main 

 reason for classing the whole group" {i.e., Truckee) "as Mio- 

 cene is that farther north in Oregon, upon John Day, Des 

 Chutes and Crooked Rivers, Professor Marsh's researches hav 

 brought to light an immense formation, computed by him to ue 

 3000 or 4000 feet thick, containing numerous vertebrate remains 

 of clearly Miocene type. These Oregon beds are all in inclined 

 position, earlier than basaltic eruptions, and the main material of 



9 Am. Jour. Sci. 3d. ser. Vol. 9, p. 52, 1875. 



10 Observations on the Faunae of the Miocene Tertiaries of Oregon. Bull. 

 IT, S. Geol. Surv. of the Terrs., Vol. 5, Article 3, 1879. 



11 U. S. Geol. Exploration of the Fortieth Parallel, Vol. 1, p. 423. 



