THE AUOH.-EAX FOKMATKJX OF THE ABUKUMA PLATEAU. ^11 



observed either in Aljukauia, or in the upper courtse of the Teiirù- 

 gawa in tlie province of Shinano. 



The Takanuki series is so named fr()ni a villaue in the vicinity 

 ol which tliat complex is typically dc\elo[>ed. The whole series 

 is divisible into two parts; the (^/) upper (UTA), embracing»- tlie 

 multifarious alternations (_)f the titanite-ampliibole scliist and biotite- 

 gneiss ; the (ß) hnver (L T A), being c(jmposed of a thick mass of 

 various gneiss-mica schists and gneisses. The occin-rence of the lower 

 sid)di\ isioii lias 1)een already alluded to in examining the line of secti<)n 

 of the ^alvayama pass/ where the beds :4and vertical, but dipping 

 in tlie |)eripheral portions of tlie series towards the middle pcjint, 

 so as to produce a. f;in-shaped structure of the Mont ]>lanc tvj)e. 

 Here, however, the schists make a low arch with their mt.in axis in 

 the riortli-south direction, and the line of section runs olJiquely 

 across the strike of this doine-sha])ed mass. 



The rock iirst met with in coniinu' westwards from the «''ranitic 

 arc'i of the district boundary is the up[)er member, which forms a 

 sm-.dl synclinal at Shimo-Matsukawa, and is intruded U]ion by another 

 boss of hornblende-granite. At Shiino-Matsiikawa we find still the 

 titanite-ampliiliole schist (U T A) Avith a dip towards the east at low 

 angles ; and not far from this point, the hnver niember (I> T A) 

 finally makes its appeurance, keeping the same dip and strike as 

 the upper. A highly (piart/.ose, brownish, graijulitic gneiss, ac- 

 Ci)inp;inied Ijy a micaceous schist with plenty of garnet, is found 

 all along the road for a distaiice of (i km, until we come to the 

 west of Takanuki. (Jften the whole complex has Ijeen so disturbed, 

 in \;!rit)us ways and at numerous points, by the intrusion of 

 biotite-granite, as to mnke <jne alnuj.-it believe the granite to be 



1 >Seo p. 203. 



