512 GEOLOGY 



contrast with them in others. The formations in eastern and western 

 Europe, as in eastern and western America, are notably unlike. In 

 western Europe, two great series, or systems, are included under the 

 Carboniferous, namely, (1) the Lower Carboniferous, chiefly of marine 

 origin, and (2) the Coal Measures or Carboniferous proper, deposited 

 partly in lagoons, marshes, and lakes, and partly in the sea. These 

 two systems correspond, in a general way, to the Mississippian and 

 Pennsylvanian, respectively, of eastern North America. 



The relations indicated above do not hold for eastern or for southern 

 Europe. The Upper and Lower Carboniferous formations of southern 

 Europe are like the Mississippian and Pennsylvanian of western North 

 America, to the extent that they are chiefly marine. The formations 

 of eastern Europe are not closely analogous to those of any part of 

 North America, the Lower Carboniferous being partly marine and 

 partly non-marine and coal-bearing, while the Upper Carboniferous is 

 largely marine. 



Like the earlier Paleozoic system, the Lower Carboniferous of 

 Europe is thicker in the western part of the continent than in the 

 eastern, though the difference is less conspicuous. In Russia, where 

 most of the preceding Paleozoic systems have had but a fraction of 

 the thickness which they possess in western Europe, the Lower Car- 

 boniferous attains great development. 



Though the rocks of the Lower Carboniferous series rest conform- 

 ably on the Old Red Sandstone, or on other phases of the Devonian 

 system, in many parts of Europe, they nevertheless record consider- 

 able geographic changes. The early Carboniferous formations of 

 western Europe are of marine origin, while the Old Red Sandstone 

 is believed to have been accumulated in inland basins. Furthermore, 

 the distribution of the Lower Carboniferous and Devonian is some- 

 what unlike, the younger formation occurring at some points where 

 the older is absent, and vice versa. Among other geographic changes, 

 a very wide-spread submergence of northern lands in Europe and 

 Asia, as well as North America, may be noted. 



Fig. 233 represents the general relations of land and water in Europe 

 during the period. Fig. 234 shows the same relations in France and 

 its immediate surroundings in more detail. In general, the relations 

 of the Lower Carboniferous to the Devonian indicate a somewhat 

 wide-spread, even if slight, submergence at the opening of the Early 



