1 2 1 1 1 3 1 1 1 1 1 2 3 Observation of Geomagnetic Total Force and Self-potential at Kusatsu-Shirane Volcano T.Koike 1 I.Suganuma 2 T.Uesugi 1 I.Fujii 1 H.Takahashi 1 K.Ikeda 3 N.Kumasaka 1 T.Ookawa 1 T.Oowada 1 T.Tokumoto 1 1:Kakioka Magnetic Observatory JMA 2:Seismological and Volcanological Department JMA 3:Kanoya Magnetic Observatory JMA GPS 1989; Fujita et al., 1995; 1996 1989 1992 1992 1996 Ohba et al., 2000; 2001 Johnston, 1997 Sasai et al., 2002
Utada et al., 2000; 1996 Hashimoto et al., 1995 Hase et al., 2003 Rapid Fluid Disruption (Johnston et al., 2001) 1976 20 3 2003 1994 1997 1982 1983 Ohchi et al., 1987 1989 1992 1992 1992 1995 2002 1997 300mV (1) (2) (3) (1) 1976 (2) (3) 1994 10 2 2.1 1
2003 10 6 9 No.1 21 20 No.18 G-856 2.0m 10 5 5 60km 5 1 1988 2003 1989 1992 ( No.4 13 19) ( No.7 10 11) 1996 No.13 19 No.7 11 1996 2 1996 2003 10 No.4 No.4 P No.5 1997 10 nt No.6 2001 35 T P Q R 3 1 P 1 Q R 5 2001 10 Q R 2002 10 0.5 1.0 30 3 1992 Q 1997 R P Q R
2 Q R 1km P 1998 7 10 1999 5 1998 10 Q R 2 Q 12 12 1 169 R 12 10 1 143 2
3 (Y) 2.2 1991 4 10 2 T No.7 11
13 19 1996 (a)1991 1996 (b)1996 2003 (a) 300 100 2.9 10 6 [Am 2 ] (b) 300 600m 2.8 10 7 [Am 2 ] (a) 1992 (a) 1989 9 1991 9 900m 5.3 10 7 [Am 2 ] 3 3 2 2 2004 5 1999 10 2003 11 Q R 3 Q 2000 8 2003 7 R 1999 8 2003 7 1nT 3 Q R Utada et al.( 2000) R 0.5 1.0 2002 10 2003 10 1 3 4 10 1 0.1 Q 5 Q R
R -25 25 0 0.6 6 R (Y) 7 Q R 2
Q R 7 5 T Q R Q R Q R 7 Q R 2.3 2 1996 1996 (a)1991 1996 (b)1996 2003 1989 1991 ( 4 ) (a) (b) 1996 1996) 1996 2 1996 Q R R Q 3 Q R Q R Utada et al. 2000 Q R 3.1 1994 1997 10 2003 10 7 9 8 1983 SPB
A C 1994 8 + 1983 SPB A B C SPB C A 8 + 55 15 1997 Line1 Line2 Line3 1994 100m 1m 3 3 SPB A B D E 8 145 20cm 50m m 500m 3 500m SPB B 1 2 GPS 10m
3 3.2 3 2.84 V 99% 7.3mV 7.3mV 1 266 8 522 9 (a)spb A B C SPB (b)c A SPB SPB SPB SPB -78mV SPB -78mV C A SPB SPB C A 9 mv m 10 (a) 10mV 40 50mV 1994 1994 SPB 10 (b) 1994 a-b 10 (c) 1994 A C -50-70mV 1997 2003 1994 2003 SPB 1994 A B
10 SPB A B D E 11 SPB SPB B 0 44 B E SPB B 1-0.64mV/m B 100mV 46 60(+300mV) 70 84(+220mV) 94 110(+360mV) 119 132(+140mV) 112 118(-180mV) 132 145(-230mV) 46 60 +300mV 1997 +300mV 11 SPB E
SPB B 12 50m 100m 2 0.93-53mV 12 11 4 18 SPB 12-53mV 13-0.64mV/m 13 20mV 1983 100mV 12 13 1983
3.3 (1) (2) 2 1997 1994 2003-0.64mV/m H Ishido and Mizutani, 1981 H 1.1 D E H 1.5 3.6 H 3.0 1983 Ohba et al. (2000) H H 10 m 100 m 10 1996 1 m 1996 2 0-180mV -230mV 500m +300mV +220mV 600m +360mV 1997 1996 600m m
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