72 ?• Kawasaki 



Tertiary formations of Hokkaido, Kyfishu and the Joban district of 

 Honsliil are the main sources of supply of coal in Japan, while those 

 found in the Mesozoic strata in Kii and Nagato are poor. Petroleum 

 occurs chiefly in the younger Tertiary of the Inner Zone, forming the 

 oil-fields of Echigo, Akita and Hokkaido. Sulphur-deposits are also 

 found on many volcanoes. 



I'art II, 

 Geology of Korea, 



By 



Shigetaro Kawasaki, 



Director of the Geological Survey of Korea. 



The geological features of the Korean peninsula agree in general 

 with those of North China and South Manchuria, and diifer in many 

 respects from those of the Japanese Islands. 



Synopsis of Stratified Rocks 



Pre-Cambrian 



Pre-Cambrian Sedimentaries 



Igneous Contact 

 Pre-Cambrian Gray Gneisses 

 UnconforQnity of dip 

 Chosen System (Lower Cambrian to Middle Ordovician) 



Parallel Unconformity 

 Heian System (Upper Carboniferous to Earlier Triassic) 



Unconformity of dip 

 Daido System (Lower Jurassic to Cretaceous) 

 Lower Daido Formation (Lower Jurassic) 

 Unconformity of dip 



