PART 1: STRATIGRAPHICAL GEOLOGY 



GEOGRAPHIC DISTRIBUTION OF THE CANADIAN AND 

 ORDOVICIAN STRATA IN MANCHURIA 



The Canadian and Ordovician strata of South Manchuria are 

 generally developed adjacent to the Ozarkian ^ and Cambrian and 

 therefore are limited to the south side of the watershed between the 

 Hun and Tai-tzu Rivers, thus occurring south of Mukden. (See map, 

 pi. 1.) Their outcrops maj^ be grouped into two areas, one chiefly 

 on the two sides of the Tai-tzu River and the other in the southern- 

 most part of the Pechili district. Moderately extensive outcrops are 

 also found near Aigawa and Tung-chia-kou in the Kuantung district. 

 As far as I know, no Ordovician strata occur in the extensive pre- 

 Cambrian area between the Chin-chia-cheng-tzu region and the 

 Tai-tzu-ho district. In addition, a small outlying basin of Ordo- 

 vician strata is reported by J. Hata in the vicinity of Kuo-chia-tien 

 Station, 135 miles northeast of Mukden. 



The Eopaleozoic strata of South Manchuria occur chiefly in struc- 

 tural basins. Although the outcrops of the older beds fail to form 

 complete circles and are much faulted, the strata ranging from the 

 Sinian Tiaoyutai to the Ordovician Ssuyen formation are in general 

 arranged concentrically around the Wu-hu-tsui, Yen-tai, Pen-hsi-hu, 

 and Niu-hsin-tai coal fields. The arrangement of the Hsiao-shih 

 and the Tien-shih-fu-kou fields, which also show a basin structure, 

 is much less regular, owing to a greater degree of faulting. In the 

 Pen-hsi-hu field, not only the Permo-Carboniferous strata but also 

 the reddish to purple, tuff aceous sandstones and conglomerates of the 

 Cretaceous (? ) Penhsihu formation were deposited in the basin im- 

 mediately on the Ordovician. Throughout all North China, South 

 Manchuria, and Korea, the coal, which is Permo-Carboniferous in 

 age, occurs in these structural basins, which, notwithstanding con- 

 siderable vertical and horizontal faulting, retain enough of their 

 original shape to cause a concentric arrangement of the outcrops 

 of the contained beds. In some of these basins a thick Sinian series 

 initiates the sedimentation on the Pre-Cambrian gneisses; in others 

 the first inundation came in Lower Cambrian time; but in no case 

 does the Ordovician rest directly on the gneiss or even on the Sinian 

 sediments. In none of these basins are there any beds between the 

 Ordovician and Carboniferous and, as stated, sedimentation first took 

 place in the Pen-hsi-hu field supposedly during the Cretaceous. 



* After thia bulletin was submitted for printing several of Kobayashi's papers ap- 

 peared, and conspquently certain of the Ozarkian names used herein must give way to 

 his terms. For example, Pingchou becomes Wanwau. 



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