ῒΐ  /*  (,**/)
 -  +1-ῌ+2, ῕ ῔GPS  ,***  1  +.  

     ,
 

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.,**- / 1 0 ,- 1234 ,**/ / . 0 ,2 1256

Crustal Deformation Associated with the July +., ,*** Eruption of Miyakejima
Volcano Detected by GPS Measurements
Nobuto BANDO῍, Shinichi KARIYA῍, Fumiaki KIMATA῍, Shigeru NAKAO῍῍,῍῍῍, Jun OIKAWA῍῍,῍῍, Eisuke FUJITA῍῍῍῍, Koji KAWAI῍῍῍῍῍,Hidefumi WATANABE῍῍, Motoo UKAWA῍῍
Takeshi MATSUSHIMA῍῍῍῍῍῍, Rikio MIYAJIMA῍ and Takashi OKUDA῍
Based on GPS data at adjacent +/ stations, a process of the ,*** eruption at Miyakejima volcano is analyzed
for the period before the ﬁrst phreatic eruption on July +.. Consequently the following results are obtained : +)Deﬂation was remarkable up to around a caldera collapse with a small eruption on July 2. The observed data are
explained by a deﬂation source of 7+.,8+*2 m- in volume, which was located - km south west of the center of thesummit (i.e, the formerly highest peak of Oyama) at 0 km in depth. The location was close to the ﬁrst deﬂation
source detected by the kinematic GPS data on June ,1, suggesting that the deﬂation started on June ,1 at around
0 km in depth (Meilano et al., ,**-). ,) After then the volcano inﬂated slightly at a shallower depth, and resulted
in a phreatic eruption on July +.. In this period, however, the deﬂation at 0 km in depth is assumed to havecontinued with a rate suggested by an exponential curve ﬁtted to the data during June ,3 and July 2. The inﬂation
during July 2 and +, was considered to be +.-8+*1 m- in volume, which was located , km south-southwest of thecenter of the summit at -./ km in depth. The shallow inﬂation source was just below the source of low frequency
tremors (Kikuchi et al., ,**+). It suggests a close correlation between the inﬂation source and occurrence of thetremors.
Key words : ,*** Miyakejima Volcano eruption, spherical source, deﬂation, eruption process, magma intrusion,
GPS measurements+ῌ ῐ ῎ ῑ ῏BC ,* /@DE<FG;HIJKLMN +32- /OPQ

9:(;<=>? 0* /@A +3.* /4 +30, /4 +32- /R4 SOG;TUHVWTUXYZ[A\]^_E4 `a.0.ῌ20*, bc defg
bc hihijklimno
Graduate School of Environmental Studies, Nagoya
University, Chikusa, Nagoya .0.ῌ20*,, Japan.
a++-ῌ**-, pqpg
phirsmnt
Earthquake Research Institute, University of Tokyo,
Bunkyo, Tokyo ++-ῌ**-,, Japan.
uv : a23*ῌ**0/ wx(dyz^ ,+ { -/ wx(hi5i|
Present : Faculty of Science, Kagoshima University,+ῌ,+ῌ-/, Korimoto, Kagoshima 23*ῌ**0/, Japan.
a-*/ῌ***0 }~doimnt

National Research Institute for Earth Science andDisaster Prevention, Tsukuba -*/ῌ***0, Japan.
a+*.ῌ**./ pqg |Hydrographic and Oceanographic Department,
Japan Coast Guard, Chuo, Tokyo +*.ῌ**./, Japan.
a2//ῌ*2.- (dhihij5imno
Graduate School of Science, Kyusyu University,
Shimabara 2//ῌ*2.-, Japan.
Corresponding author : Fumiaki Kimatae-mail : kimata@seis.nagoya-u.ac.jp

³EQ´{Q^µQ_Q¶`QabQ·`QcQ¸¹QºQ»Q¼

174

 

,***  0  ,0   !"#$%&



' GPS

( )*+,-.

/0 ,*** 1234 - 526( 7, km 8 9*./ km :#;<=>?@  AB@

 0  ,0 C GPS D-.

E +* cm F/* G@`Y/ GPS  (XY93}
:;@ <2Gt#j" 1  +. =O =>0 C^
?@$v/ 93}

A@

/ GPS 8 3-*/3 PBCR  3-*0* PDECR

]? - ?F?@] (Kaidzu etal., ,***) = Fig. + F  (,**-) A

,1 

1GC=HF/?2 0  ,0ῌ,1 s IJ

1HIDJKH 1  2 :#;@ KpF/ 1  +. ' 2  +2  0 L<L 1  +. MN.=3O P

. KpMN w@2Q  ,**+R 2  +2 SM! +/ km F/3

OP^"K G@W /

2 #$%TU&.V (XY 0  ,2  2 Z[\/$%w J$\]
.

/ Q|~ *,00 8 PBE]='^  1_(]`Y/$%abac

CR $%R PUkawa et al., ,*** ; SQ )"KC*+dY /

,**+R = Fig. + F T ¡ 1  2 s 1  +. 

eDfg * ,*** 1

=>¢ UDZ( PV5WRh@  0  ,0ῌ,1 1 `Y/ijk

$%NXw@De( PV5Y£R)c) (Meilano et al., ,**- ; Ueda et al., ,**/)

P^

Gl1`Y/m,nop 1_(¤\$%U¥¦§=0 ]`Y/q"ijkc) (Nishimura et al.,n;#@,**+ ; Ito and Yoshioka, ,**, ; Furuya et al., ,**- ;Murase et al., ,**- ; Yamaoka et al., ,**/) r-/v

m,n1yr- \]2¤\ /* Z @`( G

m,nD]¨Mm,[ P© Q

 ,**+R 'ªU«¬­ (Kumagai et al., ,**+) ®¯  ,*** s.`Y/t/u0
w xt%' GPS (//FD 4Q(,**,) 2 93}Q|*~/ GPS ;"d° \]2 9

/ P2z{"|"C`Y/opm,nhs± 1DC

|}3|~Q  ,*** ; 4Q  ,**,R5  (,**-) 2678 1*\C]Om,n=r-@/ <2 +331

 +333 ²D GPS ;"xt%;"

Fig. +. Time series of the ground deformation detected by GPS measurements and ground tilt in Miyakejima inthe period of June-August, ,***. Remarkable eruptions are shown by arrows. (A) Baseline coordinates andline length between the GPS sites of 3-*/3 and 3-*0* (Kaidzu et al., ,***), (B) ground tilt at MKE, same as
the GPS site of *,00 (Ukawa et al., ,***).

GPS¡\( ,***  1 - +. .;<=dz789:

 3./ km

175

% +ῌ, km &'() * +,***  ! "#$, ,***  / - +/ῌ,, . 2 - ,1ῌ-+ .

GPS /0123%45&6789: ;<=>?
=$@A(BCDEF;<=G%HI  

% .., km &'( (Nihsimura et al., ,**+))
JK LMNOPQRS ,*** !, TU
VWVX2YZ[&'() Geshi et al. (,**,) \] +.03  ^_`abA&'cdLe
VWVf ghLeVWV ijkldm!nZ &'()"o!, 1 - 2 . pq1rst^_ 1 - +. .
uv wxny%z {|}~ ,**+ *!
#$'& |~ (,***) 

NN

NQR~ (,***) \( GPS /0'&~ (,**,)

(

f f 9%\()Fig. ,. Location map of the GPS continuous sites
on Miyakejima Volcano, discussed in this study.
Open and solid circles indicate the sites withsingle and double frequency GPS receivers,
respectively. Contour lines represent every ,*m in height.

, GPS  1  +. ( GPS()¡¢, ;<==£+/ ¢!¤¡¢ £¥, ¦:^§¨b ¡©ª

Table +.

Station coordinates, receivers and organization of GPS sites in Miyakejima.

StationID

Longitude*(N)

Latitude*(E)

Height**(m)

Receiver

Organization

*+3+
*+3,
*,00
*,01
*/33
*0**
-**2
-**3
-*+*
-*/3
-*0*
3**/
CND
LNC
MAR

+-34.32,+-34//,.
+-34/-.1+-34/.+3+-34/0+2+-34.122+-34/.0.
+-34.2*2+-34.3+0+-34/*-2+-34/.1,+-34.2*1+-34.102+-34/+,+-34//2/-.4*10--.4+*3-+-.4+*3-+-.4*1..2-.4*3-12-.4*1/12-.4++1.,-.4*/22/-.4*3321-.4+,+*0-.4*/3++-.4*01-2-.4*1-32-.4*1++3-.4*1+3*

-+3
,*,2.
-1/
,3
.*
/.
0
01
-2
-.
,+
.0-+

Furuno MG,++*
Furuno MG,++*
Furuno MG,++*
Furuno MG,++*
Tri.***SSI
Tri.***SSI
Ashtec Z-XIIAshtec Z-XIIAshtec Z-XIITri.***SSE
Tri.***SSE
Tri.***SSE
Ashtec Z-XIIAshtec Z-XIIAshtec Z-XII-

NIED
NIED
NIED
NIED
GSI
GSI
ERI
ERI
ERI
GSI
GSI
JHD
ERI
ERI
ERI

* : WGS2. system,** : above sea level of Tokyo datum
NIED : National Research Institute for Earth Science and Disaster Prevention
GSI : Geographical Survey Institute
ERI : Earthquake Research Institute, University of TokyoJHD : Hydrographic Department, Japan Coast Guard

²³B´!"µ¶CD·¶EF¸¹º'»'¼F

176

    

 +,



  0    ! "#$% &' ,@ ,2 P 2./ $&$ ,1 +. 2 GPS  , '7 8 9):" . gKaidzu et al., ,*** ; ()"*+ - ,-./ GPS  0 Fig.

!"# ,***i/ Tx )@ Fig. + &'P;'&, 12/ 3$ 4 56.78$

+Ky 1  2 f,, /* cm 0q./9:;;< 2.;=0 Table + >2/ +5"?2. GPS 

Fig. + 12Ky x )@w//$ 3

@ / A+$ 0 A $&cd2./ lQ ,*** <=r

  ID ,B." ,@C . ADB0

2r,@}5 +}5"

$/  -*/3  -*0* @ 3 " */33  *0** @ 30 "EF/m  x )@=%$
. g# ,**,i/,@ 4 56. + 7%)3T,,P >%+c0=,E@!"  #2.T$ 0  ,3 &'?2r"f. 1  2 (,***) % E@   f, Y0 30V(2./ +5

GEHIJ# (,***) K.LMNO0$/ P

Meilano et al. (,**-)  Ueda et al. (,**/) KQ 0EFQ GPS $2.R$%+ S,-./ ,1 U&' ¡ .¢+*1 m- Pz{|}5"

T7 G@ U&'5 -῍. cmῌyr V

V(./ Tz{|}5= 2.nl'(.WXYZ[\Y]$2.^_`ab[\Y.x )" ,2 P $ GPS  +,j£]cd?)Pef. gh*# +332i/ $&$ j./ 3¤ pq¥@ ,3 &'$/ T+2.()" , k)0,lm f $ )-"()

,* cm .2.T&' [\Y]cd?)@ R$%,2.T2./



S- Dday 0C12= - /ῌ Cnl'./ $"o TT,

Dday¦D*§A¢g+¨expg¨gDayiῌBii§C@^_`ab[\Y]cd/00n1$+/Day : 0  ,3 &'

U&',@ 0  ,0῍,1 pq2rs;+o©©(+)

D* : 0  ,3  t3u3vw/+x )" / TTª«¬ 1  3῍+0 ()56.x )

x )@ 0 %)y4%) - z{|}5"V(E  $=­®K.V(.~ w/,6,-./ TKy+ )@¯°0±¤/ @$   -**3 g'A

Fig. -. Temporal changes of the horizontal coordinates at -**3, -*+* and *,00 GPS sites in the period from June
+2 to July ,1 after Nakao et al. (,***). Figures (a), (b) and (c) are observed data and exponential curves
ﬁtted to the data in the period of June ,3-July 2, and (d), (e) and (f) are residuals of observation from theexponential approximation.

N, ,*** § 1 1 +. 2op¼OabcGPS -*+*  *,00     ῎ Fig.
-!" #$%&'() -**3 -*+*

*,00 *+3+ *  +,-./ Fig. .

 !" 0  1 1 0 234#$%&/( 5678
9:;<=0> RMS ( +* cm /?@A-./BC , D(E:>0,F/GH IGHJῌ" K

177

Hst  opqr
M3 #$%&3

GPS

!,"

9%&NP(

῏,/ghH," #$%&M( ++ῌ+- 2
)M῍9<H opqr9$%&,/ KM
2G +, 2," #
k9 ++

ῐ(>3῍,"   1 1 +. 2jk k3!," Fig.

 1 1 + 2-.3LM ,NO /P;+

.

*%&

,k !

) *+3+ M3 ++ῌ+- 2@A +* cm

9S  F , 2A5673 T8U8M!

῍

," u W(P 2 2K

,V(WXGHJ "

Mk9 +* cm /W(GHE:>Q,(9R "

1 1 2 2KM3T8U8MY/ZVY)O 1 1 2 2KM .* cm h) *,00 M3 ++ῌ+-2῍3 M:v +. 23 , cm 09H(k93[\]/ %&M^/ mm, #$%&M(^+* mm _K," 1 1 / 2KM@A3`'T8





,"

Ukawa et al. (,***) 3 Fig. +  !NO0¡¢£6

GH ,*** §op

U8M,NO0abc9d/ ef~¤¥¦N,abc

/ghH," . '¨©6ª«&" N,/ ¬~5

G Fig. - GH(iHGNO 1 1 1 2jk
0,/3E:>0P +* 2jk0,/­®¯ 1 1 2 2GHWE9° 2 1 +2 2
KM@A¤¥c¨©±²9 ,*** §op³´µo¨©6ª/¶·," F@!st`suv 1 1 +, 2wxWEv

A ¸9k !¤¥c9!" 3*y!,) -**3 M*z -," G F@Aw¹, 1 1 2 2GH +. 2

) -*+* Mz +ῌ, cm, *z

KM@A3 Fig. +  !NO¸stz¤¥Y3QlmnYGHopqrabc

cm, y!,,ῌ- cm, y!,) *,00 Mz +ῌ, cm

 !" FHc{|}~3 Gc9ῐ
GPS,F/9iHGM," !0;

Mop_º9`»uῐqr

Fig. .. Time series of the vertical coordinates at -**3, -*+*, *,00 and *+3+ GPS sites in the period from June +2
to July ,1 after Nakao et al. (,***). Figures (a), (b), (c) and (d) are observed data and exponential curves
ﬁtted to the data in the period of June ,3-July 2, and (e), (f), (g) and (h) are residuals of observation fromthe exponential approximation.

~d!!!! !!!!!9!9!

178



 GPS  

!"#

2XY4

,-EFZG[\]^( Fig. / ($%&'&()*+$,- 

0 . ,3 /ῌ1 . 2 /HI Fig. 0 ( 1 . 2ῌ+/ /HI

1 . +, /(0123456 789:;<=(34 _[\]^(`4ab 1 . 2 /G01(> +, /6 +. /(?@ABC_ cZGde!fghi,-jkl-6 1 . + / 0 / "m)( $ *+no6
D( 0 . ,3 /EF 1 . +/ /GHI(GPS

EFJK

2LM(JN4 G

O 1 . 2 /G( PQ

2%&'&

*+R STU$ $,-EF PQVW

EF1pqWrs 1 . 2 /GHI ,-[\]^R & mm Vt(uuvwx

G> 4yz PQ%&'&A({|RX}FFig. /. Residuals of the horizontal displacements at each GPS site in the period of June ,3-July 2. Standard
deviations of the residuals in north-south and east-west components are shown as error ellipses of thehorizontal vectors.

Fig. 0. Residuals of the horizontal displacements at each GPS site in the period of July 2ῌ+/.
the same as in Fig. /.

Error ellipses areGPS =>I. ,*** ¹ 1  +.

 1  2
1  +*

 + cm 



!"#$%&'() *+ +,,KLº»º¼*+179]M:yz?.R{OP4&|[\]^_mnb./ }6 ~&Tvῑ ῔m./- )./Fig. 1  0  ,3

. 1  2

012. 1  2

*+. 1  +,



*+


0  ,3/
0  ,3- 1  2 


34 GPS =>&GH2?*

34 ,* cm 56.78+{ 78 (Mogi, +3/2) `a9 *+#:$;<=>2?/ @A?/ Fig. 1e, f `a?ΐ T

78 9 *+BC) #:ΐ012.]u{

2ῌ+,

ῌ1  2ῌ1  2

 1  +, $;<,- / cm D.

ῐE*+F

T/78 Fig. 1e &2.I

GH2./
Kaidzu et al. (,***) IJ 1  2

).  ῌ#:N - km, 2 0.* km  +.,KLM:N -* km ῏?OPQR&F +* cm

+*2 m- WXB`a2./ @A 1  2

S6.*+ GPS I=>2?/ T 2

4`a2.ΐ Fig. 1f &2.

3

UV&KL OP4WXY +*3 m- I ῌ##: , km, 2 -./ km WXYῒ +.-56.Z-)[\]^_`a2b.

+*1 m-`a2./  ) ΐ2(Nishimura et al., ,**+ ; Ito and Yoshioka, ,**, ; Furuya

WXYῒ¡¢£¤¥¦z./ V&

et al., ,**- ; Murase et al., ,**- ; Yamaoka et al., ,**/)/

῔& §ΐ¨F©? Furuya et al. (,**-) ª"

cdGe.  fg*῎hI. GPS =>ijJ *+=>t«"&῔b.:¬ { ­ OP R4&=>2?*+k4l@(,**,)῍mnb)b  (Kaidzu et al., ,***)/ [2®+¯- km ° ±./ ²F³῍)ij&\ ] ^ _ o p  k 4 q r s t u  v ῑ  ? Ito andz./

Yoshioka (,**,)

 +.

Murase et al. (,**-) IJ 1  2

34 w34x`a2.[\²

Meilano et al. (,**-) `ab.ΐ

῔& ´µ +* m  /** mb=>¶

4·¸ vῑb)b/ `a?ΐ2

Fig. 1. Location map of the deﬂation and inﬂation spherical sources and ground deformation calculated from thepoint source models in the periods of June ,3-July 2 and July 2-+,, ,***. Figures (a) and (b) are observed
horizontal displacements, and (c) and (d) are observed vertical displacements, and (e) and (f) are locations of
the deﬂation and inﬂation spherical sources and calculation of horizontal and vertical movements.

¶6'Y'+'¡7'·g'89'¸g':;'¹'º"'»"'¼;

180




 

!"#$ %&'((,**,) ) * +,! !"-./0123 +./ km  4 56 4 78,9 - +.,:+*0 m-  ; <=)>0?@ABB

-CDB5)E FG !" HI
JKLM25

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NB  !" HIO)P78Q R6  0 S ,0ῌ,1 

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Meilano et al. (,**-)  Ueda et al. (,**/)<=0%&'( (,**,) 3YB512 3./ km FG"-M
2 Z5 %&'( (,**,) -  
!"B [\]^T_ +ῌ, km  `aT_ b3[B5c)>52
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

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123?x B53 ,1 yzvB
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!"#- %&'( (,**,)

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FG rs!" -3.
Miyasaka et al. (,**/) - J ¡ ¢/£ ¤¥#Be'

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3 ,***¦`§¥¨©ª« "J ¬­¬®¯°,* $% >&25 GPS

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)

0 km

JKL 

]02 5  +330ῌ+333
""#Fig. 2. A cross-sectional view of the pressuresources obtained. Open and large gray circles
represent the deﬂation and inﬂation point
sources discussed by the present paper, respectively. Small gray circle and star indicate
the locations of the deﬂation source estimatedfrom kinematic GPS measurements on June ,0ῌ,1 by Meilano et al. (,**-) and the hypocenterof long period seismic wave on July +. by
Kikuchi et al. (,**+), respectively. Open ellipse shows the location of the inﬂation sill
source estimated from the GPS measurements inthe period of +330ῌ+333 by Nagoya University
et al. (,***).

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¬ 1 S +. 

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181

m    ,-'  Meilano et al. (,**-)-

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/!"#$

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 !"#$2  !"#$ %&,) '(2> L?y{U'  =12?yM)*+!,- . /,01 2 

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" , km,  -./ km, &'_ +.-+*1 m- ,-' ./ 45'67

8Ukawa et al., ,*** ; 9: ,**+; ,

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GPS 5 "+zVm@ #9Kn

- km -h'67

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m@67  <=a?@> F"!@6¤¥¦§¨©?@9:wª¨©«fz+x. noCF"! 8i?: ,**+; pqfF"!

¬Oy­z>.Ykz0®$MP.ru£>(Kumagai et al., ,**+) Dr'67  <=a?@>7\7PS

GMT(Wesseland5MPDr'EsF"!V A9Smith, +33+) MICAP-G 8 x:¯{ +333;

FGHO V@J.IJHOKL/  G![|±²³®q´µ)+ 8}~ ,**,; >m4,-@ -./ km 12@ ¶@6 ='P}·J¸@L. =

8IJ; HOMNL P'  <=a?@>.

 ,ῌ- km P'

=MP 12OB

@ 0 %&,*** PtQ KRuSMP ) .
0  ,3 DO 1  2 !"#$ >vk 1  +. 

2TwxUV>Wu ans7
6 GPS D ?y5"+z>{X@ 5'?y>|Y}Y~ZL  1  2 
5[.\J/  +* %&.12>
L/  +, 12.2 +* cm +L +) 0  ,3 MP 1  2 

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P A9" - km,  0.* km, &'@6+.,+*2°+) * + ,
Fujita, E., Ukawa, M., Yamamoto, E. and Okada, Y.
(,**,) Cyclic jerky opening of magma sheet and caldera
formation during the ,*** Miyakejima volcano eruption,
Geophys. Res. Lett., ,3, +-,0, doi : +*+*,3+,** GL*+-2.2
Furuya, M., Okubo, S., Kimata, F., Miyajima, R., Meilano,I., Sun, W. , Tanaka, Y. and Miyazaki, T. (,**-) Massbudget of the magma ﬂow in the ,*** volcano-seismic
activity at Izu-Islands, Japan. Earth Planets Space, //,-1/ῌ-2/.
Geshi, N., Shimano,T., Chiba, T. and Nakada, S. (,**,)
Caldera collapse during the ,*** eruption of Miyakejima
Volcano, Japan. Bull.Volcanol., 0., //ῌ02.
<{y: B :¹: º:\»¬¼

182º;{_@ Jx-LM|-N[»(¼N(,**+)  3/ +,+ῌ+,2.
Ito, T. and Yoshioka, S. (,**,) A dike intrusion model inand around Miyakejima, Niijima and Kozushima in,***. Tectonophysics, -/3,+1+ῌ+21.
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Sagiya, T., Yarai, H. and Imakiire, T. (,***) Crustal
deformation associated with crustal activities in thenorthern Izu-islands area during the summer, ,***.
Earth Planets Space, /,, ix-xviii.
 

 (,**+)  ,***  !" #$ ++* ,*.ῌ,+0.
%&'()* + (+332) GPS,-./0123456789:;<9<=  , /+ +1+ῌ+2*.
Kumagai, H., Ohminato, T., Nakano, M., Ooi, M., Kubo,
A., Inoue, H. and Oikawa, J. (,**+) Very-long-period
seismic signals and caldera formation at Miyake Island,
Japan. Science, ,3-, 021ῌ03*.
Meilano, I., Kimata, F., Fujii, N., Nakao, S., Watanabe,
H., Sakai, S., Ukawa, M., Fujita, E. and Kawai, K.
(,**-) Rapid ground deformation of the Miyakejima
volcano on ,0ῌ,1 June ,*** detected by kinematic GPS
analysis. Earth Planets Space, //, e+-ῌe+0.
Miyasaka, M., Nakagawa, M. and Nakada, S. (,**/)
Magma plumbing system of the ,*** eruption of Miyakejima volcano, Japan. Bull. Volcanol., 01, ,/.ῌ,01.
Mogi, K. (+3/2) Relation between the eruption of various
volcanoes and the deformations of the ground surface
around them. Bull. Earthq. Res. Inst., Univ. Tokyo, -0,
33ῌ+-..
>?@ ABCDE F!G"H(#$  I%&  "JK  L'*(  )*+,-.K (,***) /M ,*** 01 23 +, 4N#OP56QROP3S TU
V/M ,*** 7WXYZ8[9,O
P\ 30ῌ+*,.
Murase, M., Nakao, S., Kato, T., Tabei, T., Kimata, F. andFujii, N. (,**-) Dike intrusion process of ,***
Miyakejima ] Kozujima event estimated from GPS
measurements in Kozujima ] Niijima Islands, central
Japan. ,**- AGU Fall Meeting.
:^_"#"# #OPN;`"#OPabc"#"# #OPN (,***) GPS ,dZe1,],*** f<g=hiZ
e1 (+33/. 3ῌ+333. 2) > 23 j?@ABkl
C:^_"##D;`"#OPabc"##D (+332) GPS ,dZhiZem21

1+ 2.ῌ
 n+33/ῌ+331 o ?@ABkk
2/.
EpFq-FG (+333) e1!Hrs6tuv
 MICAP-G wI  , /, +*+ῌ+*-.
J Kx- yLMz {_+@ A|-}$N~O P QR S[(,***) hiZe1]"# 7WN#OPa
T mUD GPS 8V
!H #k? ,*** 4"kA+/.
NW(DN *XYFG
"YZR[D\ (,**+)  ,*** ]]E^_`] #$ ++* +02ῌ+2*.
Nishimura, T., Ozawa, S., Murakami, M., Saiya, T., Tada,
T., Kaidzu, M. and Ukawa, M. (,**+) Crustal deformation caused by magma migration in the northern Izu
Islands, Japan. Geophys. Res. Lett., ,2, -1./ῌ-1.2.
Ra(  R S  %b&   c  defghN i5j k|-}$(,**,)  ,*** ,e1111 //ῌ0/.
l OPam¡no (,**,) ¢£8¤ -D pq ¥¦§+.2 p.
Ueda, H., Fujita, E., Ukawa, M., Meilano, I. and Kimata
F. (,**/) Magma intrusion and discharge process at theinitial stage of the ,*** Miyakejima activity inferredfrom tilt and GPS data. Geophys. J. Int. (in press).
Ukawa, M., Fujita, E., Yamamoto, E., Okada, Y., andKikuchi, M. (,***) The ,*** Miyakejima eruption :crustal deformation and earthquakes observed by the
NIED Miyakejima observation network. Earth Planets
Space, /,, xix-xxvi.
~r  |-}$  N~O  ¨N©K  sª«(,**+)  ,*** hiZ¤v
3I+¬­=;®6¯°±1 #$ ++*+2+ῌ+3*.
Yamaoka, K., Kudo, M., Kawamura, M., Kimata, F. andFujii, N. (,**/) Long-lasting dike intrusion in the ,***
eruption of Miyake-jima Volcano ] Where did themagma come from ? ] J. Volcanol. Geotherm. Res., 01,,-,ῌ,.,.
N²& (,**-) ,*** ?
³´]tuµv¶/·´¸w  .2-/ῌ.,.
Wessel, P. and Smith, W. H. F. (+33+) Free software helps
map and display data. EOS Trans. Amer. Geophys. Union,
1,, ..+, ../ῌ..0.
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