JOURNAL 



OF THE 



ELISHA MITCHELL SCIENTIFIC SOCIETY 



VOLUME XXIX OCTOBER. 1913 No. 2 



GEOLOGICAL HISTORY OF WESTEEIST IN^ORTH 

 CAROLINA 



BY JOSEPH HYDE PEATT 



The State of North Carolina is divided into three physio- 

 graphic divisions, which have been designated as the Coastal 

 Plain, the Piedmont Plateau, and Mountain region. That 

 part of the state lying to the west of the Blue Ridge is in the 

 Mountain Region. This includes the Blue Ridge and the Great 

 Smokies and the country between, which is cut across by numer- 

 ous cross ranges separated by narrow valleys and deep gorges. 

 The average elevation of this region is about 2,700 feet above 

 the sea level, but the summits of a great many ridges and 

 peaks are over 5,000 feet, while a considera:ble number of 

 peaks have a height of over 6,000, the highest of which is Mount 

 Mitchell with an elevation of 6,711 feet. Over the larger part 

 of this region are to be found the older crystalline rocks, 

 gneisses, granites, schists and diorites that are pre-Cambrian age 

 which are greatly folded and turned on their edges. On the 

 western and eastern borders of this mountain region, approxi- 

 mately along the line of the Blue Ridge and Great Smokies, 

 there are two narrow belts of younger sedimentary rocks, con- 

 sisting of limestones, shales, and conglomerates, and their meta- 

 morphosed equivalents, marbles, quartzites, and slates of Cam- 

 brian age. 



The sedimentary rocks have been formed from sand, gravel, 

 and mud which have been deposited as the result of alteration 

 and erosion of the older rocks. 



By the present position of the rocks we are able to obtain 

 records regarding the order in which the rocks of western iSTorth 



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