CHAPTEE IX 



THE CARBONIFEROUS SYSTEM 



THE materials for a history of this period are more ample than 

 those available for the preceding periods. Carboniferous rocks 

 occupy a larger part of the British Isles than the rocks of any 

 other system, and in the search for coal they have also been more 

 extensively studied and explored, so -that it has become possible to 

 trace the lateral changes which the component members of the 

 system undergo, and to correlate the strata of different districts 

 with much greater accuracy. Carboniferous strata have also a 

 considerable extension in France, Belgium, Germany, Silesia, and 

 Russia as well as in Spain. 



The records of the period are indeed more complete on the 

 continent than they are in the British Isles, for they carry the 

 history of it to a later date in geological time. Continental 

 geologists have found it necessary to divide the whole system into 

 three series, of which only the two older are represented in Britain, 

 so that we have been accustomed to regard the Carboniferous System 

 as consisting of these two, a Lower Carboniferous and an Upper 

 (or Coal-measure) Series. The advance of comparative geology 

 makes this view and our insular nomenclature no longer tenable, 

 and we must either give new names to the British divisions or 

 accept those current on the continent. 



Dr. Vaughan has proposed the name Avonian for the southern 

 type of the Lower Carboniferous, and the name Bernidan has 

 been used for the northern facies.* 1 No good name has yet been 

 proposed for the rest of the British Series. 



French geologists have adopted the name Dinantian for their 

 Lower Carboniferous Series, but it is less comprehensive than the 

 British Avonian. For the higher stages it will be convenient to 

 adopt their names, and others again are used by Russian geologists 



a It was first proposed by S. P. Woodward (1856) for the whole Lower 

 Carboniferous Series, and afterwards by Lebour (1877) for the greater part. 



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