58 



N. Kaneuara 



the Mikabi] is not always clear. 



The rocks belonging to this Series are distributed over the islands 

 of Honshu, Shikoku and Kyushu, forming a distinct zone along the 

 Pacific coast of South Japan. The nature of the rocks and their 

 stratigraphical order varies in different places. 



Koto classified the schists of the Chichibu district as follows : — 

 Upper Sambagawan : — Epidote sericite-gneiss, 

 Middle Sambagawan : — Spotted graphite-schist and spotted 



chlorite-schist, 

 Lower Sambagawan : — Normal sericite-schist, intercalating 



graphite-schist and piedmontite- 

 schist. 

 In the middle of Shilvoku, the following divisions were made by 

 Prof. T. Ogawa : 



(In descending order) 



Besshi Beds 



tipper 



Lower 



Oboke Beds 



1. Graphite-schist and chlorite-schist ; 



2. Chlorite-schist, gi-aphite-schist and piedmontite- 



shist ; 



3. Calc-amphibole-schist, amphibole-schist, garnet- 



sericite-schist, garnet-am phibolite, chlorite- 

 schist, graphite-schist, glaucophane-schist and 

 piedmontite-schist ; 



4. Sericite-schist ; 



1. Chlorite-phyllite and graphite-phyllite ; 



2. Oboke- gneiss and schist. 



(B) Mikabu Series : Heretofore the Series has been known as 

 the lower division of the so-called " Chichibu System ". The rocks 

 consist essentially of pyroxenite or amphibolite with phyllites, often 

 accompanied by limestone and quartzite. Phyllites are classified into 

 chlorite-, graphite- and quartz-phyllite according to the predominant 

 component minerals. 



It recurs almost always together with and overlying the Sambaga- 

 wan Series and forms a long zone occupying the outer or southern 

 side of the latter. 



