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SECTION BIG BALDY TO DEER CREEK 



Fig. 22.15. Cross section of Wasatch Mountains east of Provo. Reproduced from Baker, 1959. 



and considers their lithology, this surmise seems doubtful — no uplift 

 in the site of the Uinta Mountains appears to have existed at this time. 

 In the Ogden segment of the Wasatch Mountains the Taylor and 

 Ogden thrusts were formed as indicated in section A-A' of Fig. 2.14, 

 sometime preceding the Willard thrust. The Willard thrust is considered 

 Montana in age, so therefore the Taylor and Ogden thrusts are probably 

 Colorado. They were then cross folded with axes trending east-west, 

 as shown in section B-R'. The cross section may also be interpreted to 

 mean that the beds were folded before the thrusting. Since the cross- 

 folding involves a different framework of stresses it seems probable that 

 , the two were formed some time apart. However, for the present they 

 will both be considered to have developed during the Colorado epoch. 



Montana Phase (Early Laramide) 



The deposition of the Echo Canyon conglomerate (Williams and 

 Madsen, 1959) and a related sequence east of Henefer (Eardley, 1944) 

 over 8000 feet thick marks a major phase of orogeny immediately to the 

 west. It began in latest Colorado time and ran its course well into the 



Montana epoch. The Willard thrust seems to have formed at this time as 

 well as the major Charleston-Deer Creek-Strawberry-Nebo line of 

 thrusts. Figure 22.15 by Baker (1959) shows the extensive, flat-bottomed 

 thrust sheets of the Provo section of the Wasatch Mountains, and Fig. 

 22.16, the Nebo thrust at the south end of the Wasatch Mountains. 

 The interpretation rendered in Fig. 22.4 suggests a great gravity slide 

 for the thrust salient. It may be noted that the sheet is made up largely 

 of the thick Oquirrh formation of Pennsylvanian age, described in 

 Chapter 6. 



The broad folds of the Oquirrh and Great Rasin ranges nearby, as 

 well as the Sheeprock thrust (Cohenour, 1957) possibly formed in 

 Montana time. See Fig. 22.13. 



Paleocene Phase (Mid-Laramide) 



The Currant Creek conglomerate (Fig. 22.5) rests unconformably 

 across the beveled edges of older formations at the southwest end of the 

 Uinta Mountains and although not definitely dated paleontologically is 

 called Paleocene by Rissell (1959). It marks the first rise of the Uinta 



