BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Vol. 34, pp. 469-494 SEPTEMBER 30, 1923 



IS THE CHANNEL OF THE MISSOUEI ElVER THEOITGH 

 NOETH DAKOTA OF TEETIAEY OEIGIN?i 



BY JAMES E. TODD 



{Presented Ijefore the Society Decemljer 29, 1921) 



CONTENTS 



Page 



Introductory 470 



Acknowledgments 470 



Doctor Leonard for the affirmative ; , 470 



Discussion of arguments 473 



Dr. Leonard's arguments inadequate 473 



No trace of old channels 473 



Glacial boulders near Bismarck 474 



Glacial gravels in terraces 475 



Glacial tills 475 



Boulder bar near mouth of Tobacco Garden Creek 475 



Evidence from South Dakota 476 



General statement 476 



Damming of the Niobrara River 478 



Bijou Hills divide 478 



Fox Hills divide 479 



Lake Arikaree » 479 



Glacial boulders without till 479 



Outlets 483 



Evidence from Montana 486 



General statement 486 



Postglacial erosion 486 



Difficulty of removing drift from channels 486 



The Yellowstone and Little Missouri diverted from their Tertiary 



channels 437 



Summary of evidence 437 



Provisional history of the origin of the Missouri in North and South 



Dakota 4gg 



General statement 488 



Glacial activity increases with temperature 489 



During the advance of the Wisconsin ice-sheet 489 



The Niobrara River and Red Lake 490 



Terraces ^g-j^ 



1 Manuscript received by the Secretary of tlie Society June 16. 1922. 



(469) 



