194 



ELIOT BLACKW ELDER 



but rather consists of numerous tabular remnants,^ which the eye 

 can easily combine and thus reconstruct in imagination the 

 original surface (Figs. 12, 13, 14). Such a reconstruction sug- 

 gests a region reduced largely to flatness, but with subdued 

 mountains and hills with a relief of less than 1,500 feet near 

 the divide, i.e., a state of early old age. The topography was 

 largely independent of rock structure, passing indiscriminately 



Fig. 12. — -Photograph of Green River lakes and Square Top Mountain, a remnant 

 of the summit peneplain. Photograph by C. L. Baker. 



across hard and soft members of the Archean complex and also 

 across the alternately hard and soft Paleozoic strata. In 1909 

 this was recognized as a peneplain by C. L. Baker f and Westgate 

 and Branson^ in a later paper described a similar feature at the 



^ See the Fremont Peak, Wyoming, topographic sheet of the U.S. Geological 

 Survey. 



^C. L. Baker, "Cenozoic History of Western Wyoming," Bull. Geol. Soc. Am., 

 XXIII (19 1 2), 73 (abstract). 



3 L. G. Westgate and E. B. Branson, "Later Cenozoic History of the Wind River 

 Mountains," Jour. Geol., XXI (1913), 142-59. 



