172 T. W. Stanton — Fox Hills Sandstone. 



Akt. XVI. — Fox Hills Sandstone and Lance Formation 

 (" Ceratops Beds ") in South Dahota, JSorth Dakota and 

 Eastern Wyoming ;* by Timothy W. Stanton. 



The Laramie question is a perennial problem for strati- 

 graphers and paleontologists, but with the continued rapid 

 accumulation of facts, as tbe detailed investigation of the 

 stratigraphy is carried over the entire area involved, it is 

 reasonable to hope that the problem vpill not be perpetual. 



At the present time one of the most important points at 

 issue is the relationship of the Lance formationf (" Ceratops 

 beds") to the Laramie formation and to tlie conformable Cre- 

 taceous sequence beneath the Laramie. Some geologists hold 

 that the Lance formation wherever it has been studied rests 

 unconformably ou the Laramie or some older formation and 

 that the unconformity beneath it represents a long, complex 

 epoch of elevation and erosion. In this paper evidence will 

 be presented to show that in the rather widely distributed 

 areas discussed there is a real transition from the marine Cre- 

 taceous Fox Hills sandstone into the Lance formation and that 

 sedimentation was practically continuous from the one into the 

 other and probably on through the Fort Union. 



The data to be discussed were obtained in three areas mostly 

 during the summer of 1909. One of these, which includes the 

 Cheyenne River and Standing Rock Indian Reservations in 

 northern South Dakota and southern North Dakota just west 

 of the Missouri River, was examined for coal lands by Messrs. 

 A. L. Beekly, Max Pishel and Y. H. Barnett under the gen- 

 eral supervision of Mr. W. R. Calvert. This investigation 

 aflforded an excellent opportunity for the study of the Fox 

 Hills sandstone in its typical area and of its relations with the 

 overlying Lance formation. A second area, which has been 

 described in some detail by Prof. A. G. Leonard, is along the 

 Little Missouri from Marmarth to Yule in the southwest 

 corner of North Dakota, where 1 spent five days. The third 

 area is the well known Lance Creek region in Converse 

 County, eastern Wyoming, where Hatcher made his great col- 

 lection of the Triceratops fauna. Nearly a week was spent 

 here in company with Messrs. M. R. Campbell and R. W. 



* Published by permission of the Director of the U. S. Geological Survey. 



f The name Lance formation has recently been adopted by the United 

 States Geological Survey for the " Ceratops beds " of eastern Wyoming and 

 adjacent areas. It is an abbreviated form of the term " Lance Creek beds " 

 which J. B. Hatcher applied to these deposits in 1903 (American Geologist, 

 vol. xxxi, p. 369) with the statement that the name is taken " from the 

 principal stream in the region where they are best represented in Converse 

 County, Wyoming." 



