µ& ¶ .. & 0-ῌ00& ,*** 8Structural Geology, No. .., 0-ῌ00, ,***9SEM-EBSP Lattice preferred orientations in naturally deformed peridotites obtained from SEM/EBSPanalysis

*Katsuyoshi Michibayashi,***  ++  +. * 



Institute of Geosciences, Shizuoka University,Shizuoka, .,,ῌ2/,3, Japan

Key words : SEM, EBSP, mantle, LPO, olivine,chromite, Oman ophiolite^*_/`abC*c.>defgh[OiTU 8Alam et al., +3/.9 M EBSP [Oi*SEM D#:;<=/0Zj>%& EjkZ -* lMDTUm> 8Dingley, +32.9 .k.& EBSP
[_*nJ"F*"m>% +33, * Hougho [pj/kZTU 8Krieger-Lassen etal., +33,9 Elq%rst.Y& MjtT*uYnvw[xypj& z *{|#$}~*%Y/%"Z"0 D"HU *{0/FT**  8 Schmid etal., +3339 [pj/{H& E%t
 kHTU
T%& SEM?EBSP @ABChh *.> T.> SEM-EBSP@ABC%& h 8`hA9 FTUEBSP  
 !"#$%& '()* +*,-.
/0 123456 7 8SEM9 * EBSP 8Electron Backscatter Di#raction Pattern9 #:;<=> SEM?EBSP @ABC%&   DE
#$F,-GHI J*KLM
DN*.>OPQRSTUEBSP V*,W%XY& +3/. * M.
N. Alam Z[45\]RS*GH].>45\

EBSP %& ^* SEM T45\.>*& 45\[^Tῌ|l.& defghD j' .>FTU 8 Fig. +9 defg
h%& ptst¡!F>ZD"¢*& F£¤*¥ 8Kikuchi, +3,29 SEMEBSP @ABCT%& Mdefgh¦+AghTD./DZ& Ej§¨©*Gm/ªh«¬gf*­H®¯°l& Hough o./±²|["pj 8Fig. + B9 M³´I¢³% +Fig. +Electron back-scattered di#raction
patterns (Kikuchi patterns) (A) A Kikuchi
pattern from olivine. (B) The same
Kikuchi pattern from olivine as (A)showing the [+**] zone axis with Kikuchi
patterns made by a computer simulation.
(C) A Kikuchi pattern from orthopyroxene
showing the [**+] zone axis. (D) A
Kikuchi pattern from Cr-spinel showing
the [*++] zone axis.

· 63 ·µ¶·Fig. ,(A) A photomicrograph of a Cr-spinel grain with reﬂected light. (B) a fore-scattered image of the same Cr-spinel
grain as (A). Strong contrasts of the brightness within the Cr-spinel grain resulted from di#erences of crystallographicorientations.

Fig. (A) A photomicrograph of typical high-T type of hartzburgite in the Oman ophiolite.
typical low-T type of hartzburgite (i.e. well-developed mylonite) in the Oman ophiolite.

SEM-EBSP  +    !"#$%&'()#
SEM-EBSP * *., mm +,-./
6& 012345)&
7894:;6<=>?@A4 BCDEF#&2 GH4IJ )*  
 4K 6*   L M46N O NP45)Q'(. * SEM-EBSP 
4 R NSTU OOrientation Image MicroscopePV )WX )Q- * EBSP 4 Y  Z  [ \ 7 8 N OForescattered SEM imageP )]^_`)* Y GH4a2bcCIJ )&de fAgh
Z[\78N* 
g4ij Okl Fig. ,P Figure , B J#mo/po1n Osubgrain boundaryP  +q#eQ Q* .  r` GN,Okl Trimby & Prior,stuQ (B) A photomicrograph of+333P

 : ῌ vw6xAhAy* z{@Az|}zh~g1/- 12z{@2Da/Q Az|}zh~g xAhAy*    J#~6{Ag|&/41k#&26* {Ag|)6@g  6Q )k2/e Okl : Nicolas, +323 ; Nicolas et al., ,**+ ) /2 
J#@g)6 £¤ ¡¢Pz¥¦ §A¨ ©©ª« £¤&¬6­
* z{@Az|}zh~g ®Qx
`AhAy¯ £¤&tp1e °±y¯ OMichibayashi et al., ,***P 1252/xAhAye²³C#Q 4´`¸ 64 ¸µ¶  .. ·345FFig. .
(A) Olivine pole ﬁgures for high-T type hartzburgite in Fig. - A. J-index is 2.-. (B) Olivine pole ﬁgures for low-T
type hartzburgite in Fig. - B. J-index is -.,. (C) Chromite pole ﬁgures for high-T hartzburgite in Fig. - A. (D) Chromite poleﬁgures for low-T hartzburgite in Fig. - B.

EBSP  ῌῌ !"#$
%& Figure + ' - ())*+,-./0& Figure + A 1 + B 23
4 5 ' 6 0 % +  , -     % 7 8 9 'Hough :.;<=1'>?@)*ABC34D./& =3><'+,-()ABC
E*45F  - G3 Eular angle Hy+, F, y,I 1
JK E*%& =*) - G3L '>MJ45F.NO0%=17P% HBunge, +32,I&QR S TU())* ,* V331 !"#$ 345
F7WE*& 3XYZ [\]"^_[3`'>MJ`E*a'>MJbC)*%cd`YZ
HFig. - AI 1 ef"^_[3g'>MJB +* mm
3hPE'iXj.0%d`3k lYZ HFig. - BI 'hE*& mn
o 'GpJ  ,** qr  !"
/* qr.s'W&#$3 LPO ,-'GpJ  XYZ
1t , G3,-.& + G cd`YZu H*+*I v+**w ,- HFig. . AI
x< + G d`YZ'y)* H**+I v+**w ,-% HFig. . BI&
Mainprice & Silver H+33-I  - G3 Eular angle.zMJ LPO ,-3{ . J-index 1|}*%
1J'/0. ~& =3 J-index
45F7'!3' + 1 45
F70%'p 3x'hP% H!
} Ben Ismaïl & Mainprice, +333 ; Tommasi et al.,,***I& Figure . A 3 H*+*I v+**w ,-3 J-index
2.-  Figure . B 3 H**+I v+**w ,-3J-index-., %&H*+*I v+**w ,-  cd``E*%"x3% H!} Nicolas & Poirier, +311 ;Mainprice & Nicolas, +323I&*'6J H**+Iv+**w ,-  =*i H*+*I v+**w 0'pcd`y)*% LPO ,-%1)*JP HNicolas & Poirier, +311I& ( d`1)*%k l=3,-7#@)*=1() =303'
GpJ >X$7%1E*%<& !"#$ n " 45
F7WP(M&'()3%7 EBSP  45F3W7*31G%&  !"#$ 3 LPO ,- +%7 3 LPO ,-3j16
J cd`1d` %,-.x
G=17(MJP HFigure . CῌD ; Michibayashi et al., ,I&=*i !"#$ 3`¡¢!'GpJ
 £¤eo'GpJ¥-7E*Jp%
HOzawa, +323I x33 i&(.7¦p& 
EBSP '> LPO ,-7E*4D.B
§¨'>% k3 LPO ,-1/©
1= 1'd`.ªC3!"#$ 3 LPO ,- HFig. . DI 70Feo'>MJ`E*«17JP HMichibayashi et al., ,I& E)' Figure . C 3><'
LPO ,-3 MPpcd`33 !"#$ 'GpJx ¬­723'®¯0%=17°¤456±²'>%³´()()('MJPJp% HFig. ,I& ¬­3®¯   !"#$ 7'0F07M=1¸ 65 ¸¤¥¦§ LPO




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qC.ῒῑrstD[% David Mainprice uv#w[% SEM-EBSP  !"xfy56z{#|/0}0 0 ~[%
rstD[% Christophe Nevado # YW0}0 aYZ# a%*%YZ¡¢£0_ 0
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