 b ./ » ,+ῌ-+ ,**+ Structural Geology, No. ./, ,+ῌ-+, ,**+



ῌ ῌ῍
Some Considerations on the Research History of the Paleo-Ryoke Belt(,) Takagi and Shibata’s Ohita-Kumamoto Tectonic Line *ῌ !**Ikuo Hara* and Takami Miyamoto**
Abstract : The Ohita-Kumamoto Tectonic Line, which was supposed by Yabe (+3,/) as
one of three branch faults of the Median Tectonic Line in Kyushu, has been newly
proposed by Takagi and Shibata (+330, ,***) as the boundary fault between the
Paleo-Ryoke belt and the Ryoke belt. This paper investigates reasoning (evidences andconsiderations) shown by Takagi and Shibata (+330, ,***) and Takagi et al. (,***) topropose the Ohita-Kumamoto Tectonic Line. It has been concluded that Takagi andShibata’s proposal for the Ohita-Kumamoto Tectonic Line is not reasonable in evidences and considerations.
Key words : Paleo-Ryoke Belt, Ohita-Kumamoto Tectoni Line, Asaji metamorphic rocks,
research history, Takagi and Shibata’s papers

"#$


  
 ,***      ῌ     ῌῌ  ,***             
MTL   !
!"#$%&'()*++, ""(-.) +(  /012)* +, 3 #/$4 %&#5 $4' 6 (  !"#$%&) 789+/:')+  + !;*#<=9#/>"?9+8%)+@,A9* ,B C ῌ D,**+ ,E -.  # FGH//012) I J# I +31* +32,
; Ichikawa +32+
$4'/KL9 /M22)
++,E)ῌN / 
OP34 2) ῌQ ,*** RS,***+( # 5T/8? ῌQ +330 #U(
96  ( /VWXYM2?9*,**+  - ¬ , ­`* ,**+  . ¬ ,3 ­(** ®C¯°±²
OYO CORPORATION, -ῌ+ῌ-*, Minaga, Saeki-ku, Hiroshima,
1-+ῌ/+,., Japan** a.))³(!´µa¶·¸¹º
Department of Earth and Planetary Systems Science,
Graduate School of Science, Hiroshima University, +ῌ-ῌ+Kagamiyama, Higashi-Hiroshima,1-3ῌ2/,0, JapanZ6 +3,3 E 1 7 / 89 + [:;\/$?96 
4&< 6
/]^?
 # E'K =,   >_2)`AaF6/ $ -b cd#?e2)- ,A9
fG+ #2&E @g)F#:h28ij8(
8F* ` kl/Am#]^?9SEBC?9n#$%&789 +D [:A(o9"#%&Ep#Fq,A9+ EGr/?.F* `H
I$[?9st [#u&v9kl  J
KwLE3M[#u&v9kl Nx?9st#E < n y1/@gz{2)+ /|}3i~
&O  wF&F9* ++#E6 (  + 3 P`|Q#E?F+ 2S2!  /9P`A9 0(9* #?9 2& $+R( Miller +321Sῌ). T ,***  K&KU#:'(9+ ,A9* + [:,Z6VW2&F9E  rX,rj   Y  <,A9 Z
6 +3,3  ##- #?9$+
2&
R(   EKU,A9 :IE¡&fG + klE ¢Z4 £¤4?e X#¥&K&z, ¦ [#¥& ;\[:?e Z\§#)F89 :h/]=8ij8(¨* LS© ¢^ª _«8¼ 21 ¼¨ º»ῌ»¼º
῎

 
   
  !"#$ %
& '( )*     +,-.)* /0 1$ 
12!  "ΐ 34 #5
$% 605 7.  8&' 2!
(7 )*349:+,
 - ;0<.1  7.  +,
/ =,10ῌ>1 2 ?+3,/@  & 1 ?A
456' C78DEF
Bῌ31@
3 ?9:GῌH;GῌH<IG@ =>J
? / K> H;@J? ,* K9:@ ,* K AL BC 45MAB
31DEF1G,5 N 0>1OP0 J8DE H 45
IJ QKL7E ?R@ +,SMTN .U OHVWP
U5X0>1L7EQRYZ S
[[U\Z T] ῐ$ ^_`UUVa5P7.  8 28
 &\Z T] ῐ$bWP῍X
YZc7 P [ #UVa50ῌ>1 d\ῌ]^?+330,***@ _ '`eC῎ af1g 8c bc d
Vg 8c ῎Wh ie[j0[k῎ lQX0ῌ>1fg hῒ7bi
m7jka51
11%no Pp11
ῌῌ
d\ῌ]^ ?+330 ,***@  0ῌ>1
MTL q)7. '`elr  MTL 8mC`eCns7. ῑ1
 _ 0ῌ>1 8DE MTL q)
7.tu8 ohpva
w# .1, q# xr
8lsaQt# xr &$ 7yls zu ῔a18g ,l 77.  .  ῎v{|w }
, x"X +321 *~ya5῎v ῎z S{tu 0[f1 |} 7.  
῎v ~(   +320+321 *  .xr
 ?῎v @ %7 ῎vnie [ +321 * ῎v O + k῎ a5tu   ῎vohO +332 * 0 ῎v xra511 xr =,], 11x"῏.,  18lL7. % ῎v l`῎z f1 {|w O7 TNH῎[ῌ῎ . cc {|,8 ".17.
+ ῌ
MTLd\ῌ]^ ?+330@  &ABῌ31H1@q)7.U MTL 9: ?Ichikawa +32*@ UV# MTL 0ῌ>
1 ?2 +3,/  ; \^[ +33, @
% ῌ
7.$ k῎Ws¡1 H1 ¢ f1 bW
g 1 Y1 7.£[ d\ῌ]^ bWa51 YV ¤1
1 v¥ 0[ ¤11 ¢ 7:ῌHῌC1:5C 1 ¦* {|7 H11:51 bc
 4W§la5x +,1?e.g. \[ +31+ ; ^[ +311 ; ¨[ +311
; Hara et al., +33, ; ^ +33/ ; ¡© +332 @ ¢£4¤ ?¥¦§ +330@ 7 H1"¨ ?+3/*@ HCNªS© H© «ªCN j«¬%a51 ^[ ?+311@  &7:CC W)*$ ῎¬.U H1 ?H
1@ %:{|w ­y1 ­D5X
Kobayashi ?+3.+@ 7:CC ®P
?H1@ "¨ ?+3/*@ H© «ª
HC "¨ ?+30+@ HC ®V
N7:CC  MNC j«N ¯?+303@ \ ?+31,@ Sugisaki ?+31,@ gq# {|, H
©0°3  TNm ¯±ªH
 Ernst ?+31,@ H©0°34°H1 ?H1@ Benioff zone 1²57.
 ?³± ^[²+311³@ c ^[ ´7  ´S  H1© 7:µSbc1 H¶µ¶7. h[ µ¶·c7 !·¸7. vV
1 ?¨ +33- @ ¸; +31* *¹X¹
Kobayashi ?+3.+@ "¨ ?+3/*@ H1 ?H
1 HC@  ºc 1 ῑa511 7. [ d\ῌ]^ v¥@
0[ # ABῌ31H1q)7.[ ABῌ31 MTL ῌ# MTL0ῌ>1nd\ῌ]^ ?+330@  &MTL 0ῌ>1?2 +3,/  ; \^[ +33, @ %

¼ 22 ¼

 $

./ ¸

MF]¹º».¡¼P ῍ 

+3,/  ῏  +33,  +3,/ ῏       +  !    " #     
+3,/  $%& '() !*+, -./01
!1# 2 +, 3"##$
2 %& %&4'(5 ) *26+,5748#95:+;./<
=0
>
1?@A#BAC## 20 
+3,/ 34῏ +33, 

5DE6F7G 2>7 $H
8*I
JK)
90*
5>  ῌ: +30, 22)
?L M1 N+;<OPQ =R +31*  S>9 : TU
?G  V.0+@'W XA +310 
YZ  [5 =R +31* B7 +30/a ; =R +31* 7G  S>. : \NC
D1# EF]@'Wῌ^
WG 6IA _HF`
I&abcde f >
JK2  +33,
2A#
gL7 $H8*I
JK)
ῌ: +30,
90*>  $() gLPM2>JKO
!*+,Nh# O*P#
+3,/  ῏ 
  S>5DE6F7EH8 1@A 5DijklmnompQR
q7E  # pQRq+@'Wῌ
rS@'WῌB7@'WTUsV 
+3-3 ;  +33, tW 2> +3,/ 1X"5 +@'W rS@'
 ῏ ?EW B7@'W
umvw  # xῌY +330 $S>9  ῏ 
TU@'WN
yZ z{A|[\ +@'W 
 +33, pQRq }~] PQA  22^# +@'WpQRqTUs_V@A
 @A[5 ,r `R N
a# > xῌY +330
z{> +33, O 
 $+@'W XA +310 YZ῏ 
2 xῌY  [5 =R +31*
ObI0cd $+@xῌY +330  ῏ 
'W\ pQRq }~] PQAB $f0 %&῏
?E ef[ gA  1 2> %& ῏ 
A>B7
῏  ThA F]ij# r
A> kA# MF]N5 N
CDl ? 7'#m nF PQA Hara et al. +33,  gA῏MF]wm 2H8B
J2 22 Hara et al. +33,  pQ
RqTUsVA+@'WῌrS@'WῌB7@'Wop 2 qRῌrs+@'gA῏MF]t'#m =u2W> xῌY +330 v ῏p\!TwK@MTL῏ 
xOTwK#8y
2>O, ῍ ῌ 
xῌY +330 O $MF]z ῌ MF]' ῍  { P ῎ [5 - |'@A ῌ MF]7{
' ( ..+῏ }+c¡¢ £S>῏S¤~sWp  0F JK9
S>9  ¥pq¦\WpW>.
'   SrI   
*#§¨ ©@A  ῍ { P < ¦\Wp $ª«¬i^WG 5 $  SrI , f
K^WGXa@A
AC ­^W\;(# 2> Yῌx +323 O®A ? 7MF]'#m +  P
'#m A ¦\Wp
QA
$+45Dixj@'WGῌ^WG NyZ=-2 $£¤~sWp N ^WG SrI  #£¤@'W¯W'°1O#± NyZ lz{A> Yῌx +323 ; : +33* ; x +33+
> £¤@'W  >@'W² f0 @'W B7@'WG\
@A l +33- ;³J@AO*y§ 2 l'WG
K9 [ S>B7*62
§O ´  # N2 $>µ2 S>K.¶HFF]
YZ5Di^WG SrI  *.1*..·*.1*/2 i
 SrI Il* 22#

 23 

ºῌ» ¼

   ῌ     +32,b  !" #$% & '(& )
*+!,-./"$!0 "12/!3#42 5 6MTL 7"42ῌ
8
 0 "/9:4( !;"4<# ->#?$2/!3 4$( MTL=ῌ8@4 5A& 6B%12C<D#@ &EF!GHῌ'(  - '&EF
! MTL 7(I!"!& J)!5"!0 "/*+(KLM2/!3 6B%
12C<D#0 "& %NOPOQ,- %
ῌ ./# (I!3 4<-M2 55(015"& J2R- ST34! 
"# U5>VI!(&  W'X
6Y7!RX8I!5"(I!3 4<-M2 . ῌZ +330 !  97:& ;< +3,/ #$"=[(I!3 55(. ῌZ +330 -  # >/2?@"4
2/!A\B& CA (I!3 #5( ].
!CA +^W'_`ab@ c/2'_`ab@^"ῌ8
Ad A\e#$;"!5"43. ῌZ +330 & 6CA fD +30-#$% X&gEFG% ""R'!"$2/! Hhῌ  +32,a0 "42 )*=W'
! #$% "&iI?$!"/ CA '!R"ῌ
Y7!3 #42 55( 5JK-
+32,a j 4<R(I!5"-?$2/!X*klL&*+RcmMnopNOq7
!R(Ir sP*k-Ir-lL?$/5"RL<*+mMQR!R(I!3 4@
4 +32, St uBT MTLvGHῌ'(  BUd( '"W'mi42iI:O<w
xy&/@M<&z(I!3 V{S(WXYZ!R(I!3 W'|[\]4<}^+32, S#*R uBTA\Bq7-/&ῌ +32,a R'
5<~(I3@W'@"/iImi4<D#&/3
@ +33, !wxs!_~92
 : 6 &`-.a( S(-1 (I!5"@  ?@I$h '7(I!"/m9-b4~2/! ^ +3103 X s42& 'c< +3/1 ; d ῌ D @ +30,ῌ ῌ  @ +303ῌ e^+31*ῌfgh fG +31- -IM<3ῌ
+32,b & -X1 'Li42< (I!, 
"~ fghj^ "sP4<3 ῌ&k +320 &\ lS( ,-/ Ma "m74<3 55"& L!nS(- +**Ma (  -  "R , 
L<5"4~42/!3 o +33+ &5$
5"@  W'0 "9p4<35 GHῌ'(  BUd( 'W'"42D#K~!M<&o +33* +33+ B5"(I!3 qy&o +33* rW';"4<  @ +33+ ; Hara et al., +33,3 Hara et al. +33, &j^"sP? 2]12/!3 W'
<lL4 : 6The Kurosegawa-Koryoke
Terrane is a continent [Kurosegawa-Koryoke continent (K-continent)] and its associated accretionary complexes with high P/T type metamorphic rocksXRelict fragments of this terrane
are now found on the north and the south of the
MTL. Those on the north of the MTL are Higo
andalusite-sillimanite type metamorphic rocks of,-/ Ma with granitic rocks of ,,3 Ma (Yamaguchi
and Minamishin, +320 ; Osanai, +33+, personal communication), Kiyama high P/T type metamorphic
rocks of -*-ῌ... Ma (Miller et al., +30/ ; Hayase andIshizaka, +301 ; Ueda and Onuki, +303), Asaji metamorphic rocks (Karakida et al., +303 ; Hayasaka etal., +323) with granitic rocks of +0* Ma (Osanai etal., +33,) and Mizukoshi Formation of late Permianage (Yanagida, +3/2)03 ?@CA &W'_`ab"?$2/!3 5$.42 =[Sr?$<
@ +33, #*(& 6& "GHῌ'(  "&?L$<sῌ8A<4~ <E<&CA @!'(I!0 "?$ LW'&tz4Ru
7?$2//3 . ῌZ +330 ui"& Mῌ +32,a '!CA2"/¡v& '@W'@"/D#ῌw¢4<x£&/(I!3 ¤+32,a & 6CAῌyz{&|}P~!
R"/!0 6#(/"/m9RI! ^+3100 ¥z 512/!(I!3#42 yz & ¦§¨©Rcª«¬ ­cB
"4 ®¯°±²³->´!Lµ c/(¶²¯·²±¸
4<!1 V{S( (I!5"- ¹G@ +33/ +330 M2q ?$2R/<3 5^ 24 ^

@2_  ./ ¶ ·¸¹ V4 º5» ῌ ῌ +330      
 
! "#$%&" ' ($#) * ῌ  +330   ῌ +32,a+,() -  +30- ./01231
68  ῌ 4 56 )7+32,a9 7 : #$;&" '* ῌ  +330  3<=>#) - ?@ A:B!C"
./#DE+F4G$%H   ῌ 
 +32,b I&'+56(J  ?./0 1  &:K)LM4 N*+*756  9 ,O '#DE+F4G$%H-P=
.Q)7 Okudaira et al., +33-' ($#)
#DE+F4G$%H &7+
FR4 /. 7' 0I&"B' ST +323  U1 ?
@23VW+ 4X5YZ[+\4  # ) ] 6 (   \  ] 6 ( Yamamoto
+30, 78  9:^;_<() *`E
\+=a$+
()7 ' bc++><(?@+U1  bc+? hῌ!dῌefgAB ST  +323 ; Dj
$ 0Ci<&"T  +323' AB?@+
Ci<&'+ k 1lE+=a)7 DjT  +323' U1
?4mFG nH4 VW " ' op48U1+^;
_<q rI&"B DjT  +323'* ῌ  +330  J s     S  T
+323 DjT +323 Hara et al. +33,  ./ T +33, K %t4 : ῌ +32,a LMNO3, #) +  ($&"' * ῌ  ,*** & PQIuv)7 &"B ' -wRN#1"S  +0. Ma ;   T T  +33-  x y z { Rb-Sr U|}~VW 7) VW3]
6X#)7 $ L&2Y J7
 4 9 ,O)7 ' Z  +330 V #$7[\qY ' #1"S
 lE($<&" ' ( ( * ῌ +330 ,***  * T ,*** h$ ] ,($ TT +33- ^_($#1"S SrI `_3 ()7 ' TT
+33-  SrI `^_+ab 4  cdVW^_ h$ab   1 lE$eI3 
4g 4 7  a8 f:
hN*&" i4 '
h$7Lj* T ,*** & -
 kbc+<v l4 1
7VW^N.Q)7 TT  +33- rm   &: 4 N*+ %H4 9  TT
+33- +,( TT n %($op+
F()7 ' \:i4 &"B' qK * ῌ
 ,*** & Z  +330 VLM&,(#$  +321 , -=#1
"S K-Ar VW ++, Ma  +321 +*-+*. Ma * T  ,*** <<79 ) 
4 N*+FR)72r&"hV;MA: f: () ,  eI3&"B' * T ,*** h$ ,O)7
: -#1"S +0. Ma 7 Rb-Sr UVW7) 7W $#1"Sst<lE #) K-Ar VWG$uZg$$)7 TT  +33-'^_$ +*. Ma 7#1"S ¡vVW st=w1 3- Ma ; +321 <31 20 3+ Ma ;  +321<<79' * ῌ  ,*** h$ -
=&  #1"S K-Ar VW u`x
y7 ¡vVW& +*-¢++, Ma : 0l
Eῌ£¤VW +,* Ma z? { N*+" 9 ,O)7 '
JcdVW`Y u7K f:|¥3
g($7 &" ' op"hg($77h¦6 &" ' f:+F0 : jT +332  SHRIMP } x § ¨   U-Pb V W  ^ _   © P T
+331  ,++ Ma  Sm-Nd VW+~6$ ?v gª§+ +*/ Ma &" ($' * ῌ  ,***  q1< 7)
jT +332 +333  SHRIMP }  VW+
(  gª§ 7)©PT
+331  ,++ Ma  Sm-Nd VW+«()7 '* ῌ  ,***  ¬­f:^2¬­F)77$^27' T ,***  * ῌ) +332
>®($¯°x±²& ³L# #$
 cdVWY u72´6L&0 ³  &
L #$2& "#$s()7 ' f: cdVW 4 
 -.Q)µ$cdVW#& I:,

¼ 25 ¼s ºῌ-» 
    
!"#$%&'  ()*+ ,-. ,***/ )012 345 6 () 7 + )9)*:;<8 7()0=(ῌ ῏῍ῌ῎>ῌ? ,+330/  @A0 A
BC()*D  !E)"#$%FG&'HIJA0K( 8**5"#$%FC , !E/ ()L
*0 ,+ +3-0/ )MNO PQM
 R  !E,-.S*/TUVW
G& )0$( ,0X. +323/+ )* 8 !E,)"#$%FY (1#%ῌ2
%33Z( MTL  "4ῌ[G&5 4 MTL \&] %)^_5(+)`'6 ((  8`'+ ) NO7Q)0=( ab 8R+c0 * 0X. ,+323/  *
5 8defghij5kjlhij
Z"#$%F89  !EUVWm:n;Do<( ,0X. +323 ; pqῌ-r
+33//+ ,-ῌs +330/ )0=5t>
? uv* + ,+3-0/ )@A 0X.
 ,+323/ !  !E"#$%FB
()6 (( >ῌ? ,+330/ 
8 !E,-.S*/TUVWG& +)0C4#ZwDQMxy' * !E"#$%FB() (C4
wDQMxEzAF* 8 !E,)"#$%FY (1#%ῌ2%3
3Z( MTL  "4ῌ[G&5 4 MTL
\&] %)^_5(+ )0{l&|G ( {l&|HDJA0
I} ( 4~A0>. ,,***/  8dJKLME\jj3A N K-Ar  +*- Ma 3A +*.
Ma  Od%KEP)6Q#* !4RSTR5 U() V'WX ,Od%/ KEP
\UlYKE,Z ([* d
JKLME\g'lYZ(]( 15 Od%JKEP
 o3^*(dJKLME4
)^_  )@ :*KE_o`aM * (Wb¡dE,*¢o3^*E_£ 5(*+ )6 ( ¤Z

>ῌ? ,,***/  8>. ,,***/ 6 5
(A0  !E"#$%FB*c d<Y¥ o%- 1*¦ef§¨*3 -.{©{lg*hOi 5+ )`*( 9,ªc«jM ( ** >. ,,***/  8-.{©{lg*hO
i 5+ )0 8d<Y¥ o% ,1#%ῌ2%/ - 1*¦ef§¨+*() k*()5 ¬ >ῌ? ,+330/  {©{lg*:_ , !EUVW/ "#$%Fl*)^_A0 ( >ῌ? ,+330/
 8R+ 8 !E,-.S*/TUVW
G& )0$( ,0X. +323/+ )u=(c0 **  !E
UVW7m*0X. ,+323/  UVW
"#$%FA()L*¢()*(( >ῌ? ,+330/ >. ,,***/ ­nopqr(# ab=5
8-.{©{lg*hO+ 8i 5+ )`s ) t<5 k45
@A0* >ῌ? ,,***/  8
!E"#$%FB*c+ t>(( =5 +330  + ,+3-0/
 8u®¯<)@A 1BE,)v°±%)²()LHIi (+ ) (w NOP)*F*( >.,,***/  8u ³xEPy$M(,pq +31* ; pq. +33,/  t<5!
³xEP~#*+ )*(( 0X. ,+323/   !E³xE_4z (´{ 8|C}T³xEP!
(+ )@* + ,+3-0/ @A 8 !E)Y¥"
C4%( ~C()LHI(+ )6 ( 0X. ,+323/  ~C"#$%F !E³xE_µ(HI 5*( ()LHIZ¬ "#$%F-¶ ·f§¨ (¸|% !E_ ()(>ῌ? ,,***/  8d<Y¥ o%,1#%ῌ2%/ - 1*¦ef§¨+ *()`* 0X. ,+323/ Q*"#$%F·f !E_ (G& ? uv*
>ῌ? ,+330 ,***/ >. ,,***/  C
4#Z
A0* * `5 {l&|G! ( >ῌ? ,+330 ,***/ >
. ,,***/ ! ¹3M: ^¼ 26 ¼» ./ »

Y&'¼+Xm ῌ  
         
+3-0  +31* !" +323 #$ %ῌ
+330 ,*** %!" ,*** &'#    ()*+,.#+,/0#12# 3 4 +,2! 056" 2#$ !" +323  #$)789%.&': ( )
;<=>?@A*BC*6+2. ,- ./" ':01 #$
2 ':$D3  E4FDG"5
6$#$ %  H789:)I
 J JB ':KLMNO+DP;<$ JJ# 5
!" +323 =. > J01#$Q J  R
S?. @A-T#$Q
%ῌ ,*** %!" ,***  U# $)BCDVHE .P;<$WX
FY.& G&'H # $)BCDVHE .P;<$WFY.J
Z[\I J  ]B ^I2
_#$Q" J `a UKLbM)c
NdeKdfgBhijN K-Ar OP +*- Ma g
Bh +*. Ma # Kb)OPkQX  + R#$W USTlU(VWlUXm YZ[_oX pH?Nqno7?@rb) \] ^HZ
_stuv;wx?@r\R#y D b)H`.& + : , =Ta
 6bBWcdze`
, 6b#
a{ T U# $)BCD
VHE .P;<X f kghi#$Q | JJ#G&'H # $)BCDVHE ..j"`a}khi#$Q lm.#$ 5  +31* no +31- B
&'~}khi#$Q 
+31* no +31-  b)5"W# |pq,r,- sWt uevwoῌ +330  |
x0J  yoL#
wo " JJ#2 %!" ,***   no ῌ]zI{ῌ][\  tF|I
B } k~#$  ῌ ,**+ #2FY.B ,  U
S , 
" S "B"6  oB3  |  JBD
2#$ | "DS "[ .2 B
 J.  +  56 W,a/" -W,  #$X t
B  +3-0 , &'H[\J
 .%!" ,*** 
U':~ # $) q b)
BCDVKLb) K-Ar OPk
Q.J"  g0Ylm61
Se# $) gBh|b)eY\" \ "\lm}k01.BX 2#$
JJ# ῌ +330 BD .KL_z IJ : KL USe ."  .2
#$W )r K) )gBh
<<) $) ]S ) jN  ῍ijN¡ )  ῍ijN¡ )#$ JB¢ 3¢£p$)῍# $)gBh£{
2#$   +31* ; no+31- J  ¤¤V¢ HE{ Okada, +30* nD BCDV.# 3¢£p$)῍# $)t¥K) )gBh<<) 
$) ]See$D.JeX 
X lm (no U¥ .
" 2 #$ ῌ +330  ¦¦BC ῍ §§ R¨© Rz}k.p
U"  gt8¨rBCDV©
8K.
e ¦¦BC῍§§ªªW8(¨©<K) 31 Ma K-Ar ij
NOP«9<?@ b)«x0.
g|©8¨r T¬R­v;v῍«¬©£ K῍®­o®R ¯i¯D῍®­YX 789#$D.P;<$FY%ῌ +330  cFY.B !
" +323 # $)789F| # $)BCDV°±789°±¯MTL j"#$ |  BCDV°±#$)789²²³´p|t¢JD.3µ#$!" +323  ῌ¶ +33/ Ia
[\ # >·#.³@¬´#$D.
%ῌ +330 . £p$)῍# $)i¯D789µ¶·<¸¸eV 3¢
 +,H¹<¹ .p BCDVµCV°±$D.  ῌ¶ +33/ῌ +330 2!ººB F

¼ 27 ¼ »ῌ


 
  ῌ +33/ ῌ +330  ! " #$% : '
 +31* ῌ +33/ $&( ') * + , -$') *
% ./01) 
2 3% 456 +31* ; ῌ +33/ ') 78292 !"#$%& ' :9;<=>(?@AB<=> '() C  ') D*EF+,-./ 3G ῌ
+33/ HD*EF IJK=>(=0?=> 
0L12#M@NO3P-QR)4 S
T +33, U6  V54U6G./06,-U)  H$W7$U) D*E
F 89X ) 12#M@NO3P- XYZ[O3P- :\/]^;./0 :
3 G <_ST +33- `G ="2῎*2^;./0ῌ12#M@NO3P-a1645b>?)'( '@)c`d
' fg*EF) e H$%
*2῎="2 ^;./0ῌ12#

M@NO3P- 3%U6 '%&hM@NO3P-)U6 iAS
T +33- ; ῌ +33/ ` G jB
2ῌklC2ῌ12#M@NO3P-ῌ^;./'( '@
0%1 mn H"#bDE6b1U6
Fo H)4.X"jB#UGp`
1HHU)*6 +qo) rH) IU6W ^;῎sJt+u@KCo`v'3P-'1U6 ST +321 ;Hara et al., +33, ; ῌ +330 H+u)LMX2῎*2῎="2῎a/2῎NX
2 fg Hara et al., +33, ; ῌ +330 H
$% ^;῎sJt+u@KCo`
3P-'E61 q wxGp1
645b>? C MTL-ῌyO]*EO*z ;ῌ +330 )Jtsz{P2 Q4 ;|B.
|}~ ` MTL-ῌJtRz{P2 Q4 ;|B.|}~ ` MTL-῍ S` o`*'( ' 6G` ^;./0
C)$WT ῌ +330 $& 
UVX"U) YZ[OTM@NO*zU+,O- W XYK G-ZX[X C HZX[XW\:,Y
Z[O3P-]X fg^;./0 1"^- _:1 `a Miyamoto andKuwazuru, +33-, +33. H^;./0_:
$GCo`ZX[X) D*EF b'JcOd $G3 Geo Miyamoto and Kuwazuru, +33- H)*EO@z ^;./0$ ]f
T%_:? C 6G`H -U
^;./0C)*EO@z)HG 4C$jB2'g3) MTL-I yO$W*1h ]jB# iyO1h ; ST +311 j $U6 Hara et al., +33, ; k) ῌ
+330 j: ῌ +33/ ῌ +330  

!
U6  ῌ +330 )
'bD1CyO ^;./0CyOl`U6 Hmn) Nῌo +330 $G)  Nῌo ,*** $G sJt#>IA)*z*EOpqUjB#:, `^;#>IA)@z*EO)12#16:
,./0` %$%6o (n Nῌo ,*** ) rssJt#./0CZ vt{u[1U6% H)yaU6%
m e sJt# '(? G`"^-ve"h)U nU6 T %῎¡1w,x¢y£¤ 4 z` o¤ 4
¥{?¦ve   §"hm LMX2῎*2῎a/2῎="2῎NX2 1¨|) S©ª} 3n H de %HU6ῌ῏῎῍
:%|U T $% MTL ) %῎¡1wG«'(U6 ` Nῌo +330 ,*** NST ,*** ~¬`­
  +3,/ z®) ¯-6 °¤ 1/ `G`±U4 z) `¢y om¤ zU4¯-6 1¨|)  %῎¡1w)²p 1
w ³&TW e+`´4U6
 Nῌo +330   4῎4]MTL
U6`y 4 z0"^-k 1¨|)µ ¶  ± MTL )kU¯ 1¨| p b>?
6 ·$G¸¹o Nῌo %῎¡1w) MTL b>? 
-o  %῎¡1wx -º¼ 28 ¼ 

 ./ »

KGfVW.d#¨a© ῌ  
 MTL῍  !"#$%& '()*+,-+./& 0123 MTL 4567$8/9   : ;     # $ %& < = 8 > ῌ ?
+31.& Hara et al. +32* @ABC;.& DDE8& MTL  .F84G!H" A<A& DC;G!IJ/
K#
L$%&/ +31* '#.(MO).C=847$B
NAB :$/& 4*+PQ R*+,-G!.(.
C=8 / 0+M& DC;
G!/& / /S& / 12  .T8
S34U5. MTL VWA8XY$B
Miyashiro +31- /& MTL& 67
& Z89
 !.:; slab"& :[\]^
surface faults _;A& <=9/
MTL .`=8>?AB;ab"@c8
Miyashiro +31- AB./& MTL .`=8C#4FO)D.d#EG! G!IJ
eF /& MTL   Gf& <=9 FO)D.d#EG! G!IJ
eF / A<A& g. MTL "DC;hH
ijIMk;D/l7$#=8B"m] O)D.d#
 :$/& E"G!#JK& +31* '#.(MnN.L<.=8o8B<p MNpqr.O"
I=8PQAC; >s< +31- <=9t9RuvSTwU1x+<pyzV{?
9$O) MTL .`;C;.|D=8D
"G!& >ῌ? +31. 01 MTL 4"W;{?9$D"G!& }.>ῌX +31. YuvSTw~
uvSY' + 
U1x+<p'(yzV{?9$O)
 MTL .`;C;.|D=8D"G!ABD./& Z +31- [\.C=8]^7$B _.`Ap& DC;#ab
"c#d=B  A"ebE
f,[& :#g R<p8& hi<;<S.gj DD"ab
. F  8 /&  /  T k l
&   ῍  +3,/ @./b8hYj$%p i.m
<=8& z  A key words / no
=B #Vno& RVno& U5Vno.F8& no"F",
 A=8B  .T8/& no/TE834 key words & /A/& . A/& D$ij" key words A8/pA :A8/& IA.q^)P"A] rsh=B tu"
v9 ;_VW"$%w;D& <<]bD/=B῍ῌ

Ernst, W. G., +31,, Possible Permian oceanic crustand plate junction in central Shikoku, Japan.
Tectonophysics, +/, ,--῍,-3.
> x& +33-& _῍Gf῍<=9῍yzA +31+῍+33, /   /  +** ' & ,*,῍,+,.
& +31.& _> xῌX
#A ¡
{n& no. /& .῍++.
ῌ|}¢xῌ?}~& +31-& <> xῌX=9 F_|£ GDP :  & no. +& ,3῍-2.
ῌ }¤ ῌ  ¥¦ ῌ }
> x ῌ X ῌ 0} & +311& <=9 O)& X[ <=9 & y2]^VW& -*3῍-3*.
> xῌ§ & ,**+& KGfVW.d#¨a© + 9KGf   & no.
./.
> x ῌ ª«¬ ῌ ­ ® ῌ ¯¬ ῌ ¢
ῌ°>x& +33+& Gf± , P /  33 'v²Y& +῍,*.
Hara, I., Shiota, T., Hide, K., Kanai, K., Goto, M.,
Seki, S., Kaikiri, K., Takeda, K., Hayasaka, Y.,
Miyamoto, T., Sakurai, Y. and Ohtomo, Y., +33,,
Tectoni evolution of the Sambagawa schists
and its implications in convergent margin processes. Jour. Sci. Hiroshima Univ. Ser. C., 3, .3/
῍/3/.
Hara, I., Shiota, T., Hide, K., Okamoto, K., Takeda,
K., Hayasaka, Y. and Sakurai, Y., +33* b, Nappe
structure of the Sambagawa belt. Jour. Metamorphic Geol., 2, ..+῍./0.
Hara, I., Shyoji, K., Sakurai, Y. and Hide, K., +32*,
Origin of the Median Tectonic Line and its initial shape. Mem. Geol. Soc. Japan, no. +2, ,1῍.3.
> x ῌ }¤ ῌ 0} ῌ ³w< ῌ ´µ& +321& <=9± , P¶ῌX/   3. '·& 1*῍1+.
> xῌ? & +31.& _.
;Gf¸n4 2¹¡{ no. +& 3῍+..
 º& +33*& KGfK® /  

¼ 29 ¼  ῌ~ £31  3ῌ+-.
 +33+   31 .1/
ῌ.3+.
 ῌ  ῌ +323    !" # no. -- +11ῌ+20.
$%% ῌ &'% +301 Rb-Sr ()*!+" + , /2 ,*+ῌ,+, - +330./ - +..- p.
0 1 +310   23456(
789*2  :;< no. ,/0
+ῌ1*.
=>%! +31* + "ῌ ?#)@$ABC*DE  F%&ῌG' () *HI+ ,IJ +3-ῌ,**.
Ichikawa, K., +32*, Geology of the Median Tectonic
Line of Southwest Japan. Mem. Geol Soc.
Japan, no. +2, +21ῌ,+,.
Ichikawa, K., +32+, Closure of the Jurssic sea in andaround the Ryoke-Sambagawa region. In Hara,
I., ed., Tectonics of Paired Metamorphic Belts,
Tanishi Print Kikaku, ++-ῌ++0.
=>%! +32, + KLMN - OP
Q . .+.ῌ.,*.
&R./ῌST Uῌ  !)" ,*** +
0V1W 23 4X5 no. .3
+// p.
3Y  +303 460780 Z[(\*92]9^* _`ab0c & # no. . .+ῌ/*.
defῌ:Y/ῌg;hῌ<=ῌij>k? +331 lm@n 0(op*q
9 r#As# , 3, -+0ῌ-,0.
B':CD +30/ " (Etp* 90 no. + .ῌ+..
E
B':CDῌ u4ῌFv  +33,  
3 w Gx yHJ -1+ p.
B':CDῌIJ +32, a 1m  
6 zK9  22 /,-ῌ/--.
B':CDῌIJ +32, b " @n {|}&5L # no. ,+ +1-ῌ+2+.
B':CD ῌ IJ ~M ῌ * ῌ eEt  OPN +303 
QR # no. . -ῌ,+.
Kobayashi, T., +3.+, The Sakawa orogenic cycle
and its bearing on the origin of JapaneseIsland. Jour. Fac. Sci. Imp. Univ. Tokyo, [,], /,,+3ῌ/12.
g* +3/* + 0 ]9^*S(8]  /0 --3ῌ-...

g* +30+ 460 STm,oU/
STm +.ῌ+3.
g* +31- "V9CW X) w"Vx ,IJ ,/-ῌ,0+.
J! +3-0 %Y QX !I"  .- 1/2ῌ120.
J! +3-3 lmZG QX !O([""  .0 +ῌ+,.
J!ῌ%:?ῌ~4\ +30, G
 w Gx ]^ .,- p.
 _ +332 +78`0 WV1 +*. /0/ῌ/10.
Miller, J. A., Banno, S., Hashimoto, M. and Iwasaki,M., +30/, K-Ar ages of micas from the Sonogi,
Konoha and Kiyama metamorphic terrains in
Kyushu, Japan. Jour. Geol. Soc. Japan, -., +31ῌ,*-.
Miller, J. H., +321, The Ethics of reading. Columbia
Univ. Press !a ῌ*bN c ,*** d¡ ef g¢J ,+, p."~ £ῌ   +330 + [N O( ¤¥¤ῌ¦§¨ rῌh©4
6Sª 0 «¬ ­¨®¯¨° ijk±a) w­¨®¯¨° ²lx mD³´21ῌ33.
~ £ῌ  ῌµ ¶ ,*** ·$ῌ ῌ¸ Qno` # no. /0 +-ῌ,,.
Miyamoto, T. and Kuwazuru, J., +33-, Detrital garnets in Permian to Cretaceous sandstones of
the Kurosegawa Terrane and its geologicalsigniﬁcance. Jour. Sci., Hiroshima Univ., Ser. C,
3, 1,+ῌ1--.
Miyamoto, T. and Kuwazuru, J., +33., Chemicalcomposition od detrital garnets in Permian toJurasssic sandstones of the Kurosegawa Terrane in the Kayaba-Nishinoiwa area, western
Kyushu, Japan. Jour. Sci., Hiroshima Univ., Ser.
C, +*, +2+ῌ+3,.
Miyashiro, A., +31-, Metamorphic rocks and metamorphic belts. Allen and Sons., .3, p.
Okada, H., +30*, Sandstones of the Cretaceous
Mifune Group, Kyushu, Japan. Mem. Fac. Sci.
Kyushu Univ., Ser. D (Geol.), +*, +ῌ.*.
/ῌ  ῌp'¹ +323  º»6
¼ Fῌ@n   !" # no. -- +21ῌ+32.
Okudaira, T., Hara, I., Sakurai, Y. and Hayasaka, Y.,+33-, Tectono-metamorphic processess of the
Ryoke Belt in the Iwakuni-Yanai district, Sou-

2 30 2

:: b ./ ¸_c QR¹<bºº»¼ ῌ

thwest Japan. Mem. Geol. Soc. Japan, no. .,, 3+῍+,*.
  +33*   31 
 /1/.
 +30- /  +     +*0 p.
 ῌ !" ῌ #$ ῌ %&$
+33, '( !"#$%&'() *+, +. ,0.῍,1*.
 ῌ$) *ῌ-.+/, +33- -0.
 1/
 Rb-Sr 0 $"2'341 
23 no. ., +-/῍+/*.
45 +3,3 1  / 56 + 7687
899::6;;< = -0 /*1῍/+3.
>< =ῌ?@AῌBC>ῌ?D@C +33- 0.ABCEDFEGFHIGJK = 33 .13῍.2,.
HL I ῌ ?@A ῌ BC> ῌ JMK ῌ NOP, +33- LM9 9QRNS
T/  + U  ++/ p.
NOPQ ῌ V ῌ R S ῌ W&TCU ῌ VX
WῌXNY +33/ YZZ1[[\= +*+ 333\]'3^#"_
῍+**,.
NOPQῌVX Wῌ]^W` +330 0.B
ab_c d`Hef῍Z1::a b +*-  ,.0.
NOPQῌ?&gcUῌh dῌieῌhjk
KῌVX WῌXNY +332 SHRIMP b' f UlPb 1 
+*/  ,+..
NOPQῌ?&gcUῌVX WῌXNYῌieῌh d +333 gh i' [\\]mn_o)pjq1/
 +*0  0-.
r&ks +321 l'9mbptn
*N -2 -2/῍.,,.
o& uῌhpq, +323 1/1 vr\]7w-x::aHst::aHy = 3/ 021῍1**.
Sugisaki, R., Mizutani, S., Adachi, M., Hattori, H.
and Tanaka, T., +31,, Late Paleozoicgeosynclinal basalt and tectonism in Japanese islands.
Tectonophysics, +., -/῍/0.
uYv TwU +31- -x::a zxy.*+ p.
zp{{ +31, |}-Bab7\~|} ~H hNS ,+-3῍0,.

zp{{ῌuYCῌ&-  +31+ [<b7\~|}
 ~ 
23 no. 0 +,+῍+-0.
῍
hpq, +33+ 
r I + ( -FG
 8 X&QR
ῌw no. .* 3῍,/.
hpq,ῌo& u +330 _c  ?
 
Q\w &'# ')H,++῍,+3.
hpq,ῌo& u ,*** _c : H_c῍  23no. /0+῍+,.
hpq,ῌ&ῌ ,*** 0.
C1/  KlAr 1 23
no. /0 ,+-῍,,*.
hpq,ῌ &uw ,*** _c H : H  23 no. /0 ,/- p.
&u +33/ |}B H +*,   -+῍.0.
&uῌN *ῌ]^W`ῌBvU +33-
|}B9 ῍: Hr::Gv a = 33 ,//῍,1/.
ῌ¢ £K +311 &uῌ ¡ῌ7&
 H¡¢ ::Gy q¤w  ¥OxyQR +*1῍+/+.
?@A +31* 0.A£¦p¤¥A NS ,-1 p.
?@AῌBC> +33/ 0.Ah£ +*, 
¦§Htn
 31῍++,.
?@A ῌ BC> ῌ JMK ῌ @*% ῌ HL
Iῌ +33, ¨©9 9QRNS T/  + U  +,3p.
Ueda, Y. and Onuki, H., +303, K-Ar dating on themetamorphic rocks in Japan. Sci. Rept. Tohoku
Univ., Ser. III, +*, -+-῍-,+.
¦§¨{ +33. O<687©< ª« ,.3 p.
¬`s +3,/ ^ª#«¬­®4¯`°9
= -, ,*+῍,*3.
± ­ῌg® +320H²¯°³´bvr1H±µ¶'
²¶ 0³QN TU +/ +-1῍+/+.
Yamamoto, H., +30,, Plutonic and metamorphic
rocks along the Usuki-Yatsushiro tectonic linein the western part of central Kyushu. Bull.
Fukuoka Gakugei Univ., Pt. III, +,, 3-῍+1.
X ´ +3/1 -1 ThU µ +* 3. p.
¶&·C +3/2 hv¸§¹·C = 0. ,,῍,-+.

¶ 31 ¶