52 



LARAMII', FLORA OF THE DENVER BASIN. 



however, we have it confined between certain limits. We 

 have it above a characteristic Fort Pierre fauna and below 

 a characteristic Fort Union flora. Just how much of that 

 which intervenes is Laramie is not known. 



On another page he added : 



We found here no traces of the volcanic mate.ial of the 

 Li\'ingston formation, which only 30 or 40 miles to the 

 southwest is so well developed. 



Part of the same area was examined in 1903 

 by Stanton and Hatcher,"" whose report was 

 published in 1905. They were, however, more 

 concerned in the ehicidation of the Montana 

 group, the classification of which, as will be 

 subsequently shown, has played an important 

 part in the Laramie-Livingston controversy, 

 and they made only incidental mention of the 

 higher beds. Concerning these they said: 



South and west of Fish Creek these shales [Bearpaw] 

 are overlain by marine Cretaceous sandstones and by a 

 thick series of beds that ha\e been referred to the Laramie, 

 Livingston, and Fort Union formations. 



The generalized section for central atul north- 

 ern Montana as worked out by Stanton and 

 Hatcher is as follows: 



In 1900 R. W. Stone" studied the strati- 

 graphy and cual resources of an area of ap- 

 proximately 1,000 square miles in central 

 Montana, extending from Shawmut westward 

 to the head of Musselshell River and southward 

 in the Shields River valley to the town of Clyde 

 Park. A large part of this belt is included in 

 the area covered by the Little Belt Mountains 

 folio, already mentioned, but whereas Weed 

 recognized only four formational units in the 

 Cretaceous system, S£one was able to differen- 



'• Stanton, T. W., and Hatcher, J. B., Geology and paleontology ot the 

 Judith River beds: U. S. Cfeol. Survey Bull. 2:i7, p. 59, 1905. 



" Coal near the Crazy Mountains, Mont.; U. S. Geol. Survey Bull. 

 341,pp. 78-91, 1909. 



Cretaceous. 



tiate and map seven such units. These were 

 set forth by Stone as follows: 



Tertiary /Fort Union formation. 

 I Livingston formation. 

 Laramie formation. 

 Montana group: 



Bearpaw shale 



Judith River formation. 



Claggett formation. 



Eagle sandstone. 

 Colorado shale. 

 Kootenai formation. 



The rocks referred to the Laramie were 

 divided roughly into two parts. The lower 

 division, resting on the Bearpaw shale and 

 ranging in thickness from 200 to 460 feet, was 

 said to be composed of red and greenish sand- 

 stones. "Its age has not been determined, 

 but lithologically it belongs to the overlying 

 formation and lience it will be provisionally 

 regarded as a part of the Laramie." Concern- 

 ing the upper portion, Stone said: 



Taken as a whole, the upper part of the Laramie forma- 

 tion is distinguished from the formations above and below 

 by its light-gray color in compirison with their somber 

 hues. It is composed largely of soft gray smdstone and 

 variegated shale. The gray beds, from 1,000 to 2,400 feet 

 thick, make a conspicuous valley. * * * The gray 

 beds of the Laramie formation are o^■erlain, possibly with 

 imconformity, by somber-colored sandstone and shale 

 which may represent the LiWngston formation. Suffi- 

 cient paleontologic eWdence has not been obtained, how- 

 ever, to determine the limits of these stratigraphic units. . 

 A section measured by C. A. Fisher and T. W'. Stanton 

 On a fork of Big Elk Creek gives a thickness of 5,592 feet 

 from the base of the Laramie to the base of the sandstone 

 and grit probably of Fort L'nion age, and of 10,324 feet for 

 the beds above the Beirpiw shale. 



Douglass ** revisited the Fish Creek area in 

 1909 and published additional notes on the 

 geology, revising his previous views to some 

 extent. He accepted the classification of the 

 Upper Cretaceous by Stanton and Hatcher but 

 was still more or less confused concerning the 

 Fox Hills and the limits and extent of the so- 

 called Laramie. 



In 1909 also I ptiblished a note *" on the 

 geologic section of the Fish Creek area, giving 

 it the following interpretation: 



Above the Beirpaw is a series of shaly sandstones, at 

 least several hundred feet in thickness, that unmistakably 



"» Douglass, Earl, A geological reconnaissance in North Dakota, 

 Montana, and Idaho, with notes on Mesozoic and Cenozoic geology: 

 Carnegie Mus. Annals, vol. 5, pp. 272-280, 1909. 



«> Knowlton, F. U., The stratigraphic relations and paleontology of 

 the " Hell Creek beds," " Ceratops beds," and equivalents and their 

 reteronce to the Fort Union lormation: Washington Acad. Sci. Proc., 

 vol. 11, pp. 192-194, 1909. 



