post- Cretaceous Moiintain-inciking along its course. 193 



Considering the extent and character of the disj3lacements, 

 in part horizontal overthrusts, in the Canadian portion of the 

 Rocky Mountains described by McConnell, the conclusion that 

 tangential thrust has acted likewise in the case of the Wasatch 

 seems to be reasonable, although the results are in important 

 points different. And it can not be questioned that the force 

 which could compress and reduce to plasticity a resisting 

 Archaean mass might make great movements of Paleozoic 

 strata over an Archaean surface, inclined or not, and probably 

 give plasticity where movement was effectually resisted. 



The facts in the Wasatch and Uintah region come therefore 

 into harmony with others in the Rocky Mountain region, and 

 even into near likeness to those from the Appalachians. The 

 movement manifested was either " a thrust upward and east- 

 ward of the whole Archaean body when the Paleozoic flexures 

 took place " (p. 48 of Mr. King's Report), or its compression 

 and torsion (p. 752), or else, as another might suggest, a thrust 

 westward of the sedimentary strata against the Archaean range. 

 Metamorphic action in the overlying limestones about Clayton's 

 Peak is mentioned on page 45 as a u mechanical " result during 

 the movements. 



In the preceding explanations, the reported facts are made 

 to tell their own story. For some inferences from them con- 

 tained in the report of Mr. King I am unable to find a suffi- 

 cient basis in the facts. Among these I question the follow- 

 ing: that a full section of the Mesozoic and Paleozoic series, 

 40,000 feet, more or less, then existed in the region of Salt 

 Lake Valley, as a westward continuation of like beds capping 

 the Wasatch Mountains ; that along a fault-plane following 

 nearly the axis of the Wasatch Archaean and of its " capping 

 arch of sediments," the western mass dropped down to depths 

 equaling the thickness of the beds. It does not seem certain 

 that any great fault along this line was among the results of 

 the post-Cretaceous orographic disturbance. 



The reason for doubting is, first, the absence of direct evi- 

 dence ; for no outcrops of Mesozoic beds in the Salt Lake 

 Yalley are reported, and no proof of their presence there as 

 buried deposits is mentioned or has since been observed, 

 although deep borings have been made. Again the Oquirrh 

 Mountains and Wasatch Range are but twenty miles apart, and 

 have similar Carboniferous rocks at summit at nearly the same 

 level ; and without other sustaining facts it is hard to believe 

 that in the narrow space between such an enormous downthrow 

 and burial ever took place. 



Nothing stated is adverse to the view that at the post- 

 Carboniferous disturbance, the Wasatch Range (not a line west 

 of it along Salt Lake as the Report suggests) became the 



