642 GEOLOGY 



phalia, 274 feet. Here, as elsewhere, beds of marine origin alternate 

 with those which were deposited on land, in marshes, etc. 



In Russia, as already noted, the Lower Carboniferous contains 

 most of the coal, while the Upper is made up chiefly of limestone, 

 though in southern Russia (Donetz coal-field) there is coal in the 

 Upper division. The Upper Carboniferous limestone of Russia 

 (Fusulina limestone) is represented by similar formations in southern 

 Europe. The faunas of the marine part of the system in Europe 

 have much likeness to those of western North America, suggesting 

 that marine life was able to pass between these continents, via 

 northern Asia. 



The upper part of the Upper Carboniferous system of Europe at 

 various points and at various horizons contains bowlders, some- 

 times of large size, and beds of breccia or conglomerate of sub- 

 angular fragments. The bowlders are of granite, gneiss, schist, 

 quartzite, etc., and occur both singly and in groups. They have 

 often been thought to represent deposits made by icebergs, and so 

 to point to the existence of glaciers; but this interpretation has not 

 been established. Other interpretations, such as the transportation 

 of the bowlders by uprooted and floating trees, are tenable. 



North of the European continent, the Carboniferous formations 

 (Fusulina limestone, Coral limestone, etc.) are represented in some 

 of the Arctic islands (Spitzbergen, Nova Zemla, Bear Island). 



Igneous rocks and crustal disturbances. Igneous rocks are 

 associated with the Upper Carboniferous formations of sediment MTV 

 origin in western Europe. Their extrusion seems to have been 

 an accompaniment of the crustal disturbances which began in 

 middle and western Europe at the close of the preceding period, 

 as already noted, and continued through the Permian. 



Other continents. The Upper Carboniferous of Asia is repre- 

 sented by both marine and non-marine formations. Arnonu; the 

 former is a thick limestone, wide-spread in southern China 1 :md the 

 Malay Peninsula, overlying the Devonian conformably. The non- 

 marine phase, with numerous beds of coal, is found in Asia Minor, 

 on the east side of the Middle Urals, and in northern and eastern 

 China, reaching to northern Tibet on the one side, and to Mongolia 



1 Researches in China, Carnegie Institution, Willis, Vol. I. 



