260 BROOKS AND KINDLE PALEOZOIC ROCKS OF UPPER YUKON 



remains of fish teeth from the "Eampart series,'"' provisional!)' assigned by 

 him to the Silurian.-^ Some collections made in the White Eiver basin 

 by Brooks in 1898 and 1899 represent two horizons. One of these is from 

 an Upper Carboniferous limestone; the other was thought to represent a 

 Devonian fauna ;-" but, as will be shown, it is probably also Carboniferous. 



The valuable collections made by Collier along the Yukon in 1902 indi- 

 cated the presence of both Upper and Lower Carboniferous faunas on the 

 upper Yukon and included some imperfect fossils, which led him to con- 

 sider Spurr's "Eampart series" to be probably of Devonian age.-" Hol- 

 lick in the following year made some additional collections from Collier's 

 localities. 



A geologic reconnaissance from Eagle to Eampart by way of Fairbanks, 

 made by L. M. Prindle and Frank L. Hess^'' in 1904, furnished a small 

 collection of fossils from the White mountains. They were in part De- 

 vonian corals, with some doubtful forms, but also included a small 

 Carboniferous fauna in part provisionally assigned by Girty to the Penn- 

 sylvanian or Permian. 



The present report is based for the most part on an investigation carried 

 out in 1906, but the earlier studies have been freely drawn upon. Some 

 three weeks were devoted to a study of the section exposed along the 

 Yukon between the International boundary and Circle. At the latter 

 place the party divided ; Mr Kindle continued down the river to the Porcu- 

 pine and up that stream to the boxindary, while Mr Brooks made an over- 

 land trip to Fairbanks on the Tanana, and thence went westward, reaching 

 the Yukon again about 30 miles below Eampart. In all, about two months 

 were devoted to the investigations by both authors. The work along the 

 Yukon was much aided ])y the route map of that river made by Collier in 

 1902, which is the only one having even an approximate accurac}'. Special 

 acknowledgment should be made to L. M. Prindle, whose results, both 

 published and unpublished, have been made use of. The lack of any 

 summary of the recent stratigraphic work in this field is the justification 

 for this publication, in which an attempt will be made to correlate some 

 of the important Paleozoic terrains of Alaska. Special emphasis will here 

 be laid on the rocks exposed along the Yukon between the boundary and 



2= Ibid., note on p. 1C8. 



2° Alfred H. Brooks: A geologic reconnaissance in the Wtiite and Tanana River basins. 

 Twentieth Annual Report, U. S. Geological Survey, 1899, part vii, p. 472. 



Alfred H. Brooks : A reconnaissance from Pyramid harbor to Eagle City, Alaska. 

 Twenty-first Annual Report, V. S. Geological Survey, 1900, part ii, p. 359. 



^ Arthur J. Collier : The coal resources of the Yukon. Bulletin no. 218, V. S. Geo- 

 logical Survey, 1901, p. 16. 



^ L. M. Prindle and F. L. Hess : The Rampart gold placer region. Bulletin no. 280, 

 V. S. Geological Survey, pp. 21-2? 



