HISTORICAL REVIEW OF THE LARAMIE PROBLEM. 



67 



Laramie, were then found to be more closely 

 related to those of the Wasatch or later beds. 



In 1895 Wilbur C. Knight 34 published a paper 

 on the "Coal and codl measures of Wyoming," 

 in which he stated that coal-bearing beds'', 

 are found at "Henrys Fork, Almy, Twin Creek, 

 Hams- Fork, and Coalville [Cokeville]. The 

 last four localities are probably in the same 

 coal field, which belongs to the Lower Cretaceous 

 and has been known as the Bear River group." 

 This view was widely at variance with the facts 

 even as then understood and has not been 

 followed. 



The following year (1896) Stanton and I sii 

 spent a few days at Evanston and Hodges Pass 

 and concluded that the Wasatch was probably 

 unconformable on the coal-bearing beds, which 

 were presumed to be in the upper part of the 

 Laramie. 



In the summer of 1905 A. C. Veatch 36 and 

 party began an investigation of the coal and 

 oil resources of this region and presented a 

 short preliminary statement of results, which 

 was published the next year. The several for- 

 mations observed and mapped, with their geo- 

 logic time values, were set forth in the form of 

 a table. The uppermost Cretaceous formation, 

 with a thickness of over 5,000 feet, was referred 

 to the Laramie. It was said to include the 

 Adaville-Lazeart coal, 10 to 84 feet thick, and 

 to be terminated at the top by a marked un- 

 conformity. To the beds above the uncon- 

 formity, which included the coal at Evanston — 

 that is, the bed worked at the Almy and Red 

 Canyon mines — the name Evanston formation 

 was given, but the exact age determination was 

 left questionable. 



Veatch's complete report on this area " was 

 published a year or more later, and in this the 

 geologic and paleontologic data were reviewed 

 in full. The uppermost member of the Creta- 

 ceous section, called Laramie in the preliminary 

 report, was here called the Adaville formation, 

 which included also a white basal sandstone 

 denominated the Lazeart sandstone member. 

 A few hundred feet of the basal part of the 



« U. S. Geol. Survey Sixteenth Ann. Rept, pt. i, pp. 208-212, 1895. 



35 Stanton, T. W., and Knowlton, F. H., Stratigraphy and paleon- 

 tology of the Laramie and related formations in Wyoming: Geol. Soe. 

 America Bull., vol. 8, p. 148, 1897. 



so Coal and oil in southern Uinta County, Wyo.: U. S. Geol. Survey 

 Bull. 285, p. 331, 1906. 



•» Veatch, A. C, Geography and geology of a portion of southwestern 

 Wyoming: U. S. Geol. Survey Prof. Paper 56,' 1907 [1908]. 



Adaville formation was thought to be of Mon- 

 tana age, and the remainder of the 5,000 feet 

 was called "Lower Laramie." Fossils were 

 found only in the lower part of this formation, 

 and both plants and invertebrates appeared to 

 indicate an age older than Laramie, and these 

 furnished the basis for placing the lower por- 

 tion in the Montana. 



The unconformity at the top of the Adaville 

 formation ("Lower Laramie"), according to 

 Veatch, involved a long period of folding, 

 faulting, and erosion, inferred on stratigraphic 

 grounds and indicating the removal of over 

 20,000 feet of strata. 



In the geologic column given by Veatch 38 

 the overlying Evanston formation was referred 

 without qualification to the "Upper Laramie" 

 and made the basal member of the Eocene, but 

 in the discussion of this formation 30 this refer- 

 ence was not quite so positively stated. On / 

 this point Veatch wrote as follows : 



The Evanston formation was considered by the geolo- 

 gists of the early Government expeditions as Laramie. 

 Later Dr. White, after studying in detail its invertebrate 

 fauna and comparing it with that found at Wales, Utah, 

 concluded that these beds were undoubtedly Wasatch. 

 Ward and Knowlton, because of its flora, have regarded it 

 as essentially the same as the Carbon beds, but as the 

 stratigraphic position of the Carbon beds has never been 

 determined this correlation does not lead very far. 

 Knowlton reported that the leaves collected in 1905 are 

 "Upper* Laramie." As early as 1893 he suggested the 

 possibility of their representing the Denver beds, and 

 again, in 1898, doubtfully referred this locality to the 

 Denver. Dr. T. W. Stanton regards the invertebrates as 

 Laramie or Fort Union, and the question thus becomes 

 involved in the larger one of the true age of the Fort 

 Union, which has been regarded both as Upper Cretaceous 

 and Eocene. The paleontologic collections made at this 

 locality do not prove conclusively that the beds are Upper 

 Cretaceous or, on the other hand, show that they are basal 

 Eocene. * * * The stratigraphic evidence strongly 

 suggests that the line between the Eocene and the Creta- 

 ceous should be drawn at the base of the Evanston and 

 certainly shows no reason for drawing it between the 

 Evanston and the Almy [the formation conformably above 

 the Evanston]. On the whole, the Evanston formation 

 may be tentatively regarded as Eocene. 



The reference of the Adaville and Evanston 

 formations to the "Lower Laramie" and 

 "Upper Laramie," respectively, was in accord 

 with the section as worked out in Carbon 

 County, Wyo., even including the great uncon- ' 

 formity separating them. 



* Idem, facing p. 50. 

 39 Idem, pp. 76-87. 



