542 J. G. H. GODFKEY ON THE GEOLOGY OF JAPAN. 



34. Notes on the Geology of Japan. By J. G. H. Godfeey, Esq., 

 E.G.S., late Mining Engineer-in-Chief to the Japanese Govern- 

 ment. (Bead March 6, 1878.) 



One of the first published accounts of the geology of Japan is 

 contained in the paper read by Baron von Bichthofen before the 

 Geological Society of Berlin in 1873. 



That author stated his belief that the backbone of the Japanese 

 islands was formed by three systems of mountain-ranges composed 

 chiefly of Silurian and Devonian strata accompanied by granite. 

 The first and main system, of which the axis trends from "W. 30° 

 S. to E. 30° N., extends through the island of Kiushiu, and after- 

 wards continues up to the great bend in Nippon, the largest island 

 of the group. This first system is intersected at either end by 

 another which runs S.S.W. to N.N.E. On the west it commences 

 in Kiushiu and extends southward in the direction of the Liukiu 

 Islands, whilst on the east it constitutes the northern branch of the 

 main island, and with a slight deviation in its course continues 

 through the islands of Yesso and Saghalien. A third system, not 

 properly belonging to Japan, is indicated by the S.W. and N.E. line 

 of the Kuril Islands. The first system, jjwhere it occupies the 

 country for itself alone, is comparatively free from volcanoes ; the 

 second is accompanied by volcanoes ; but the greatest accumulation 

 of volcanic rocks as well as extinct volcanoes is found in the places 

 of intersection, or those regions where the lines of two systems cross 

 each other, and also in that region where the third system branches 

 off from the second. 



Amongst the details regarding the volcanoes of Satsuma, particu- 

 lar attention was drawn to the fact that the various families of vol- 

 canic rocks appeared there at the surface in exactly the same order 

 of succession as is the case in Hungary, Mexico, and other volcanic 

 regions, viz. : — 



1. Propylite or trachytic greenstone. 



2. Andesite. 



3. Trachyte and Ehyolite. 



4. Basaltic rocks. 



Within the last few years a careful geological survey has been 

 made of the northernmost island Yesso, under the direction of B. S. 

 Lyman*, who divides the rocks of Yesso into seven different 

 groups : — 



1. New alluvium. 



2. Old alluvium. 



3. New volcanic rocks. 



4. Toshibets group. 



5. Old volcanic rocks. 



6. Horimui or coal-bearing group. 



7. Kamaikotan or metamorphic group. 



* B. S. Lyman, 'General Eeport on the Geology of Yesso:' Tokio, 1877. 



