STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 425 



with deposits of salt and gypsum. Some dolomites, regarded as 

 equivalent to the Zechstein, were seen at one locaHty. These con- 

 tain a Permian fauna. Disturbance followed the close of the Per- 

 mian, and the overlying rocks are notably unconformable, occupy- 

 ing valleys in the eroded Paleozoic rocks. 



Conditions in the southern Urals are much as in the Donetz 

 Basin. Murchison^^ described them in his great work on Russia. 

 At a later date he gave a synopsis of his conclusions, in which he 

 states that the Permian deposits " occur in almost apparent con- 

 formity to the Carboniferous rocks." Coal appears to be wanting 

 in Urals but the lower division contains streaks of impure coal in 

 the central region between the Urals and the Volga River. 



Spitsbergen. 



Nathorst^* has given in summary the results obtained by himself 

 and others during exploration of the Spitzbergen region. The 

 whole series from Lower Carboniferous to the Permian is present. 

 The Lower Carboniferous, which is represented by the Kulm, rests 

 unconformably on the Devonian. It consists, at base, of dark 

 quartzitic sandstone, underlying yellow sandstone, on which rests a 

 mass of bituminous clays and shale with fragments of ferns and, in 

 the lower part, a thin seam of coal resting on a Stigmaria underclay,, 

 containing sphaerosiderite. Above this mass of shale and clay are 

 sandstones, yellow and white, becoming red in the upper portion,, 

 showing coaly streaks at some places and at others lenses of coaly- 

 shale resting on Stiginaria-c\ay. The lens form is due to compres- 

 sion. The dip approaches 90°. The petrographic characters as 

 well as the fossils indicate that the Kulm beds were deposited in 

 shallow fresh-water. They suggest swamps at mouths of rivers. 



The Kulm beds are followed by a mass of limestone, which, at 

 base, shows transition to the Upper Carboniferous, and at top to- 

 the Permian. The system closes with rather loose marls and sand- 

 stones, holding less than 2 meters of limestone in the thickness of 



23 R. I. Murchison, " Sikiria," 3d ed., London, 1859 p. 325 et seq. 



-* A. G. Nathorst, " Beitrage zur Geologic der Baren-Insel, Spitzbergens 

 iind des Konig-Karl— Landes," Bull. Gcol. Inst. Upsala, Vol. X., 1910, pp. 

 321, 2>22>, 325, 2>^7, 330, 227, 347-350. 



