atmospheric pressure change associated with the 2003 tokachi-oki earthquake shingo watada, takashi...
TRANSCRIPT
Atmospheric Pressure Change Associated with the 2003 Tokachi-Oki Earthquake
Shingo Watada, Takashi Kunugi, Keinji Hiarata, Hiroko Sugioka, Kiwamu Nishida, Shoji Sekiguchi, Jun Oikawa, Yoshinobu Tsuji, Hiroo Kanamori
microbarogram 2003/09/26
２４ hour
1000sec
JIZODO STS1 vault
Software configuration
Microbarograph recording and telemetry systems
Hardware configuration
GPS antenna
Sensor
Control PC
On-line board PC based systemSGN (Yamanashi, Japan)
Air batteryPortable sensor
Board PC
Microbarograph sensor
Off-line recording system
Ground verticalvelocity
Filtered atmosphericpressure
3.2km/sec
)exp( tzmxk
atmosphere
Ground
w
)exp( tzmxk
atmosphere
Ground
w
cfw
fp )(
)(
for homogeneous fluid
Observational transfer functionwc
p
Mechanical sensitivty check by shake table
cwgh
cwgh
response acoustic nt displaceme static
tableshakeFor
response acoustic nt displaceme static
ground at the wavesseismicFor
Theoretical transfer functionof long-period atmospheric waves.
)exp( tzmxk
atmosphere
Ground
w
),()(
)(kfZ
fcw
fp
for homogeneous fluid
2
/1
1
k
cwc
p
ss
High frequency asymptotefor propagating acoustic waves
Conclustion
The atmospheric pressure change associted with the 2003 Tokachi-Okiearthquake are observed at the co-located site of broadband seismometers.
The origin of atmospheric pressure change is the Rayleigh waves passing atthe site.
The observational transfer functions, both phase and amplitude, are constructedand compared with the theoretical transfer functions and found consistent up to50 sec.