468 STUDIES FOR STUDENTS 



In studying the Tertiary deposits of Kansas Haworth reaches 

 similar conclusions. He says : J 



The relative positions of gravel, sand and clay of the Tertiary over the 

 whole of Kansas .... correspond much better to river deposits than to lake 

 deposits. ... It is quite possible that during Tertiary time .... lesser local 

 lakes and lagoons and swamps and marshes may have existed in different 

 places and for varying lengths of time. But when we consider the Kansas 

 Tertiary as a whole and yet in detail, it must be admitted that the materials 

 themselves have many indications of river deposits and a very few of lake 

 deposits. 



Matthew, 2 in discussing the question whether the White 

 River Tertiary is an eolian formation, considers the objec- 

 tions to the lacustrine hypothesis and gives reasons for his 

 believing it to be of eolian origin. He reaches the conclu- 

 sion that the " White River clays in Colorado, at least, are 

 chiefly eolian deposits Most of the sandstones'are prob- 

 ably fluviatile Some sandstones may be eolian" (407). 



This position, however, cannot at present be regarded as estab- 

 lished ; but the question of lacustrine origin is shown to be an 

 open one. 



In 1897 Davis, 3 in discussing the origin of the Denver forma- 

 tion, gives criteria for distinguishing lacustrine from fluviatile 

 deposits. In a later publication 4 the same author compares 

 lacustrine with fluviatile deposits as follows : " In both cases the 

 deposits are stratified ; in both cases the deposits may include 

 fine as well as coarse materials ; in both cases the area of distri- 

 bution may be large as well as small ; in both cases the thick- 

 ness of deposits may be great as well as light ; in both cases the 

 strata may bear ripple-marks, mud-cracks, cross-bedding, and 

 other indications of small and variable water-depth. With all 

 these similarities, it would not be remarkable if a lake deposit 

 were sometimes called a river deposit, or if a river deposit were 



1 The Univ. Geol. Surv. of Kans., Vol. II, p. 283, 1897. 

 3 Amer. Naturalist, Vol. XXXIII, pp. 403-408, 1899. 



3 Science, U. S., Vol. VI, pp. 619-621, 1897. 



4 Freshwater Tertiary Formations of the Rocky Mountain Region. Proc. Amer. 

 Acad. Arts and Sci., Vol. XXXV, pp. 345-373, 1900. 



