258 BROOKS AND KINDLE PALEOZOIC ROCKS OF UPPER YUKON 



coast, Avhile Mendenhall" at the same time carried "an exploration from 

 the mouth of Dall river, tributary to the Yukon, to the Koyukuk and 

 thence to Kotzebue sound. In 1902 Brooks,^* in company with L. M. 

 Prindle, traversed the western part of this province, in course of an ex- 

 ploration extending from Cook inlet to Eampart, on the Yukon. 



These various explorations defined the larger geographic and geologic 

 features of the province and paved the way for the somewhat more de- 

 tailed investigations to follow. In 1899 McConnell began his detailed 

 studies of the Klondike placer fields, which lie adjacent to the area here 

 discussed, and continued them with some interruption until 1906.^^ The 

 easterly extension of the same general belt of rocks has been the subject 

 of investigations by Keele" and Camsell.^^ 



The detailed stratigraphic studies on the Alaska- Yukon were inaugu- 

 rated by Collier^* in 1902, who gave, however, more particular attention 

 to the coal-beariAg terrains which belong to the Mesozoic and Tertiary. 

 These studies were supplemented the following year by Arthur HoUicJc, 

 who made large collections of fossil plants from the coal-bearing beds 

 exposed along the Yukon. In 1903 Prindle^* began a systematic study of 

 the geology and mineral resources of the Yukon-Tanana region, which has 

 been continued to the present time. The gold placers being of the first 

 importance, the rocks with which they are associated, namely, the meta- 

 morphic schist, have received the first attention from him, but the Paleo- 

 zoic and Mesozoic stratigraphy' has also been touched upon in his reports. 

 Prindle's work was supplemented in 1905 by a geologic reconnaissance 

 made by Stone^" from Circle to Fort Hamlin. 



" W. C. Mendenball : A reconnaissance from Fort Hamlin to Kotzebue sound, Alaska. 

 Professional paper no. 10, U. S. Geological Survey, 1902. 



" Alfred H. Brooks and L. M. Prindle : An exploration in the Mount McKinley re- 

 gion, Alaska. Bulletin of the U. S. Geological Survey. (In preparation.) 



1= R. G. McConnell : Preliminary report on the Klondike gold fields, Yukon district, 

 Canada. Geological Survey of Canada, no. 687. Ottawa, 1900. 



Report on the Klondike gold fields, part B, vol. xiv, Geological Survey of Canada, 

 no. 884. Ottawa, 1905. 



Report on gold values in the Klondike high level gravels. Geological Survey of 

 Canada, no. 979. Ottawa, 1907. 



" J. Keele : Report on the Upper Stewart River region, Yukon. Geological Survey of 

 Canada, no. 943. Ottawa, 1906. 



" C. Camsell : Report on the Peel river and its tributaries. Geological Survey of Can- 

 ada, no. 951. Ottawa, 1906. 



" Arthur J. Collier : Coal resources of the Yukon basin. Bulletin no. 218, U. S. Geo- 

 logical Survey, 1903. 



i» L. M. Prindle : The gold placers of the Fortymile, Birch Creek, and Fairbanks dis- 

 tricts, Alaska. Bulletin no. 251, U. S. Geological Survey, 1904. 



L. M. Prindle and F. L. Hess : The Rampart gold placer region, Alaska. Bulletin 

 no. 280, U. S. Geological Survey, 1906. 



L. M. Prindle : The Yukon-Tanana region. Description of the Circle quadrangle. 

 Bulletin no. 295, U. S. Geological Survey, 1906. 



=0 R. W. Stone : A geologic reconnaissance from Circle tq Fort Hamlin. Bulletin no. 

 284, U. S. Geological Survey, pp. 128-131. 



