DIASTROPHISM AND THE FORMATIVE PROCESSES 331 



to show that the disturbance came within the later Devonian rather 

 than at its close. ^ 



These movements apparently also affected a portion of Nova 

 Scotia, for in the MacArras Brook region, according to Ami, the 

 Lower Carboniferous strata rest unconformably upon the upturned 

 edges of the Lower Devonian of that region.^ Though the folding 

 is here less definitely located than in Gaspe, both foldings would 

 seem to be manifestations of the same diastrophic disturbance. 



Evidences of the same uplift and folding are to be looked for in 

 Appalachia. Following the black Hamilton shales from New 

 York to southern Virginia there occurs a great volume of sandy 

 shale and argillaceous sandstone comprising the Jennings and 

 Hampshire formations of Maryland, or the Chemung and Catskill 

 of New York, Willis has estimated that if this mass of sediment 

 could be restored upon a sea-level plain corresponding in shape and 

 size to Appalachia, it would produce a mountain range closely 

 resembling in height, extent, and mass the Sierra Nevada of Cali- 

 fornia.^ These he calls the Devonian Highlands. Their elevation 

 would follow the Hamilton and thus correspond closely in time with 

 the folding period in Gaspe. 



At the close of the Devonian much of the continent of South 

 America stood out of water."* In northeastern Argentina, to the 

 west of the Cerro del Agua Negra, Bodenbender found the thick 

 Devonian formations unconformably overlain by red Permo- 

 Carboniferous sandstones. ^ The time of this movement has not 

 been as yet closely determined. 



But the greatest Devonide movements which have yet been 

 recognized are those of Australia. The close of the Devonian was 

 one of the greatest mountain-making epochs of New South Wales, 

 according to Siissmilch — of such importance, indeed, that the name 



' Ibid., pp. 14-15. 



^ H. M. Ami, " Meso-Carboniferous Age of the Union and Riversdale Formations, 

 Nova Scotia," Bidl. Geol. Soc. Am., XIII (1902), 533. 



3 Bailey Willis, "Paleozoic Appalachia or the History of Maryland during Paleo- 

 zoic Time," Maryland Geol. Survey, IV (1902), 61-62. 



^ Charles Schuchert, Jour. Geol., XIV (1906), 738. 



s G. W. Bodenbender, Boletin de la Academia Nacional de Ciencias de Cordova, 

 XV (1897), 201. 



