PROCEEDINGS 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. XI, No. i, pp. 27-45. March 31, 1909. 



THE LARAMIE FORMATION AND THE SHOSHONE 



GROUP. 



By Whitman Cross. * 



A recent discussion as to the origin and definition of the term 

 Laramie, by A. C. Veatch,^ calls attention once more to a vexed 

 question in American stratigraphic nomenclature. The original 

 observations, by Mr. Veatch and others, which have led to this dis- 

 cussion of terminology are certainly of great significance and must 

 receive full recognition, but they do not justify, in my opinion, the 

 proposition made by Mr. Veatch for the future use of the term Lara- 

 mie. Another course will be advocated in the following pages. 



Mr. Veatch announces the discovery of an "unconformity which 

 in the vicinity of Carbon (Wyoming) and to the southeast separates 

 all the Laramie beds studied by the Hayden and King parties from 

 the underlying Cretaceous." The unconformity may, he believes, 

 involve the "whole sedimentary series of the region, or over 20,000 

 feet of strata." This discovery and others recently made in Wyom- 

 ing and Colorado^ demonstrates that the similar unconformities 

 hitherto known in Colorado and Montana are not of such local 



' Published with permission of the Director, U. S. Geological Survey- 



^ On the Origin and Definition of the Geologic term Laramie. Amer- 

 Jour. Sci., 4th ser., Vol. XXIV, 1907, pp. 18-22. Jour. Geol., Vol. XV, 1907. 

 pp. 526-549. 



^ Veatch, A. C. : Coal and Oil in Southern Uinta County (Wyo.), U. S. Geol. 

 Survey, Bull. 285, Contributions to Economic Geology, 1905, pp. 332, 335. 



Veatch, A. C: Coal Fields of East-Central Carbon County (Wye), U. S. 



