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THE FORTIETH PARALLEL SURVEY. 



509 



Bedimcnts. There cannot be a stratified deposit laid down npon a pre- 

 existing surface, conforming to its irregularities in such a manner as to 

 present itself in the form of continuous layers. Yet Mr. Emmons 

 describes such a phenomenon: hence the only conclusion following his 

 views is that the solid granite slid up along the bottom of the quartzite, 

 bending it so as to cause it to conform with the irregularities of the gran- 

 ite, and this elevation of the solid granite must have metamorphosed 

 the limestone, and corrugated and uptilted all the adjacent formations ; 

 yet with all this the gentlemen studying the locality fail to show any 

 evidence that the granite was solid at the time. Is it possible that an 

 enormous mass of rough jagged granite could have been pushed like a 

 huge rasp in contact with quartzites, limestones, etc., and have left no 

 trace of its movement upon thenil So, too, if it were intrusive, it 

 should in like manner show by its contacts that such was the case. 

 Instead of raising so extraordinary a fabric of theory on so slender a 

 basis of facts, it would have been better to study the region a little 

 more thoroughly. To us it appears highly probable that the granite 

 was of eruptive origin, and of later than Archxan ago. It is certain 

 that the section of the Wahsatch Fuingo given in the Atlas of the 

 Fortieth Parallel Survey does not conform to the theories of Messrs. 

 King and Emmons ; and, moreover, that it represents impossible strati- 

 graphical conditions. 



Views very similar to those here expressed by the writers of this 

 paper have already been published by Professor Geikie, Director of the 

 Geological Survey of Great Britain, in an article having as its title, *' On 

 the Archaean Kocks of the Wahsatch Eange " (Am. Jour. Sci., 1880, 

 (3) XIX., pp. 303-367). From this paper the following extract is made, 

 and it will be a sufficient indication of the light in which Mr. Geikie 

 regards the geological speculations of Messrs. King and Emmons touch- 

 ing the structure and age of the range in question. 



" According to the Reports of the Exploration of the 40th Pamllol, the Wali- 

 eatoh Mouutainy consiat of ii eoutral core of Archa}au rocks, couiposed partly of 

 gnmhes and partly of various (piartzito, schistfl, and other crystalline masses. 

 These rocks are represented aw luiviiig formed an island in the Paleozoic sea ; 

 and Mr. King asserts that the island nuTst have pn'sented to the west an 

 almost precipitous face of 30,000 feet, or upwards of 5-^ miles — an altitude 

 exceeding that of any mountain chain. Kound this lofty An^lucan island the 

 whole of the Paleozoic and Mesozoic sediments are said to have been deposited 

 to a (h'ptli of from 3(),()00 to 40,000 feet, in one continuous uiiiiitcrruptcd 

 series. Sul)sc(]_uent terrestrial movements, acting along the line of the original 

 island, have u[) raised the surrounding sedimentary masses, and the ancieii' 



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