muoro.] THE WASATCH MOUNTAINS. 385 



in"- either member of the synclinal fold diverge Can-like to the eastward 

 and curve respectively to the north and south around either body. 

 The western extension of the syncline, were it not for the fault, would 

 pass above Salt Lake city. It probably lies at some depth beneath it. 



South of Lone Peak the granite sinks beneath the surface, and the 

 range opposite the valley of Utah Lake is formed of a tlat arch of* 

 Paleozoic beds, half of which has been cut oil' by the fault and depressed 

 beneath the valley level. 



The accompanying map (Fig. 18) is a reduced copy of the geological 

 map of the range in the atlas of the Fortieth-parallel reports, of which 

 Dana M says: " It is the grandest exhibition of facts pertaining to an 

 individual case of mountain building in geological literature.''* 



GEOLOGICAL PANORAMA OF THE WASATCH RANGE 



as sken J kom THB i:aiu:oai>. 



By S. V. Emmons. 



From the northern point of the range to Brigham its east front shows 

 a series of northwesterly dipping beds, ranging from Lower Carbon- 

 iferous limestones, through Devonian and Silurian, to Cambrian at 

 Brigham. 



From a distance one can distinguish the different series of beds by 

 their colors, the limestones being very dark, the quartzites light in 

 color. Thus in this part of the range the white Cambrian quartzites 

 at the base of the sedimentary series are sharply contrasted with the 

 dark band of Silurian limestone, and this again from the overlying 

 light Ogdeu quartzite at the base of the Devonian. 



The depression in the range south of Brigham marks a line of strike- 

 fault, running southeast with downthrow to the southwest, by which 

 the Cambrian and Silurian beds are repeated on the mountain-mass 

 projecting westward from the main line of the range, round which the 

 railroad bends in going to Hot Springs. 



At Hot Springs the waters issue from outcrops of Cambrian quartzite, 

 forming part of a mass of quartzite and limestone, broken down by the 

 great Wasatch fault from the beds which now cap the high peak to the 

 cast. On this peak the white line of Cambrian beds, with a thin cap of 



' The small scale of this map necessitates the omission of many topographical and 

 some geological details. It serves, however, to illustrate the genera] outlines of 

 structure as above described, and shows the western end of the broad anticlinal 

 arch of the linta mountains. 



On the western base of the range R. C. indicates the mouth of Big Cottonwood 

 canyon: 1.. e.. that of Little Cottonwood canyon. Figures denote elevation in feet 

 abOTC sea level. 



461 0E 25 



