GEOLOGICAL NOTES ON COAL AND IRON ORE 101 



Concerning the coal-area in the plane of stratification 

 it seems that those seams which have a roof of marine 

 limestone have a larger extension than those which are 

 superimposed by quartz-sandstone. The anthracites appear- 

 ing in the middle of the coal formation and just below the 

 resp -limestone have thus been met with in all places where 

 those limestones have been observed within the Taiyuan 

 basin. It is not impossible that to this anthracite zone belong 

 also the large anthracite seams in the Ping Ting region. 

 At Yang-Ch'uan, 20 li N.W. of Ping Ting Hsien, where the 

 Pao Chin Mining Company have their headquarters, I have 

 had the opportunity to study the nature of the coal formation. 

 Also here the anthracites are connected with a series of 

 marine limestones in the middle part of the coal series. 

 Whether these marine sediments represent the same horizons 

 as those at the Taiyuan basin is, however, not yet settled. 



Our present Paper deals with the conditions in the 

 Carboniferous of Central Shansi, but it ought to be mentioned 

 that the bituminous coals which occur in the lower parts 

 of the Jurassic in Northern, and also in certain places of 

 Western Shansi, are of a quite different type. In contrast 

 to the Carboniferous coals, which from all indications are 

 formed in the vicinity of the sea ("Paralische Flotze") the 

 Jurassic coals are continental deposits, formed at great 

 distance from the ocean ("Limnische Flotze") and should 

 as to their origin correspond to the Saxonian, Silesian and 

 Bohemian coal-seams in Europe. 24 (For further information 

 about the stratification of the Jurassic coal formation at 

 Ta-T'ung in N. Shansi see the above mentioned paper by 

 Mr. C, C. Wang). 



The most important iron-ores which are connected with 

 the coal-series in Central Shansi are those which occur 

 immediately above the Cambro-Ordovician limestone. This 

 ore-formation appears generally as nodules and concretions 

 very much varving in size, of limonite, sphero-siderite, and 

 other hydrated^iron-compounds; more seldom pyritic, rusty 

 limestone or hematite. These nodules are embedded ma 

 matrix of more or less decomposed, often strongly red- 

 coloured, clay-sediments or argillaceous sandstones. The ore 

 is very often found in the form of fissure-fillings or occupying 

 pockets and cavities in the ordovician limestone substratum. 



Though of an enormous regional distribution these ore 

 deposits are comparatively seldom accumulated to such an 



24 Which are of Carboniferous age. 



