JUI)» C liJj/ 



INTERRELATIONS OF THE FOSSIL FUELS.* 



II. 



By JOHN J. STEVENSON. 



(Read April 14, 19 17.) 



THE CRETACEOUS COALS. 



Coal of Cretaceous age occurs more or less abundantly in many 

 countries. The original areas in which it was formed vary from 

 mere patches to thousands, even hundreds of thousands of square 

 miles ; but these greater areas have been broken by erosion into 

 isolated basins, or better into isolated fields, sometimes widely sepa- 

 rated. The coal seams are not confined to a single horizon but are 

 present throughout the Cretaceous at localities where proper condi- 

 tions existed. The several regions have so many features in common 

 as well as so many in contrast that a detailed description of some 

 typical areas, though tedious, is necessary for proper understanding 

 of the relations. 



Europe. 



In western Europe, coal is confined almost wholly to the Wealden 

 but in central Europe the Upper Cretaceous contains deposits of 

 more than local importance. 



Coal in thin seams has been observed at some places in England 

 but the quantity is significant. The Wealden of the Dorsetshire 

 coast and of the Isle of Wight has no coal. MantelP states that, 

 at Brook Point on the Dorset coast, a sandstone ledge in Lower 

 Wealden encloses trunks and large branches of trees, mostlv petri- 

 fied. Webster, at an earlier date, had seen these stems, of which 

 some had been converted into a jetlike substance. Mantell, observ- 



* Part I. appeared in these Proceedings, Vol. LV., pp. 21-203. 

 1 G. A. Mantell, " Geological Excursions round the Isle of Wight," 3d 

 ed., London, 1854, pp. 203-206, 238, 239, 242. 



PROC. AMER. PHIL. SOC, VOL. LVI, E, MAY 23, I9I7. 



