Combined approach using the electromagnetic

Combined approach using the electromagnetic
precursory phenomena and critical phenomena for a
short-term earthquake prediction
Tokyo
We are
here!
Nagoya
Earthquake Prediction Research Center, Tokai University
Toshiyasu NAGAO
Today’s talk
 What
is “Seismo-Electromagnetics”
some examples (California and Japan)
 Greek
VAN method
 Introduction of Natural Time analysis
 Introduction of LAI (LithosphereAtmosphere and Ionosphere) coupling
What is “Seismo-Electromagnetics”
Research for electromagnetic phenomena
possibly associated with (impending)
earthquakes.
 It has a long history, however the existence of
the phenomena themselves still have a lot of
arguments.
 Best-known example is the case of the M7.1
Loma Prieta (California) EQ in 1989 (FraserSmith et al., 1990)

However………
We know that
－＞ EM phenomena preceded by EQs are so small !
M7.1 Loma Prieta (California) EQ in 1989
ＤＣ
0.1
telluric current
1
ＵＬＦ
3-comp. magnetic
10
Brown letters
Signals emitted from the lithosphere
100
1ｋ
10ｋ
100ｋ
1Ｍ
10Ｍ
100Ｍ
（Ｈｚ）
SeismoElectromagnetics
in Japan
ＥＬＦ
ＶＬＦ
ＬＦ
ＭＦ
Narrow band 3-comp. magnetic
2-comp. magnetic for direction
finding
EM pulse measurements in a
borehole
Anomalous transmission of radio
waves
Vertical E-field
measurements in a borehole
ＨＦ
ＶＨＦ
FM broadcast wave anomalous
transmission
Natural noise observation
Micro wave observation
Blue letters
Ionosphere/troposphere
anomaly
(radio wave transmission
anomaly)
Nagao et al., 2002
(J. Geodynamics)
Seismo-Electromagnetic studies in Japan
Signals emitted from the lithosphere
DC telluric current (Tokai, Hokkaido, Tokyo, Chiba Univs.)
ULF 3-comp. magnetic (Tokai, Chiba, ECU, Hokkaido, Chubu Univs.)
ELF narrow band 3-comp. magnetic (Chubu, Naoya Tech. Univs.)
VLF on-land magnetic direction finding (Tokai Univ.)
VLF borehole electromagnetic pulses (Kyoto Sangyo Univ.)
Broad band (VLF-VHF) electromagnetic field (Osaka Univ.)
Micro wave (JAXA, Chiba Univ.)
Ionosphere/troposphere anomaly
VLF-LF radio wave anomalous transmission (ECU, Chubu Univ.)
GPS-TEC anomaly (Chiba, Tokyo Gakugei, ECU Univs.)
VHF FM radio wave anomalous transmission (Hokkaido, Tokyo Gakugei, Tokai
Chiba Univs., ECU, Okayama Univ. of Science)
Atmospheric electric field (Tokyo Gakugei, Waseda Univs.)
Underground Electric field (Akita Pref. Univ.)
Lab. experiments
Tokyo, Tokyo Metropolitan, Osaka, Tokai Univs. JAXA)
Izu 2000 events (volcanic eruption and intense seismic activity)
3-comp. magnetometer array
Activity
started
Izu 1998-2000
Eigenvalue (λ3, 0.1Hz)
Izu Pen.3-comp. Mag array.
E-field Niijima (0.01Hz)
1998
1999
2000
Telluric current record
Collapsed station
at Kozu Island
July 2002
VAN method




Greek scientists, Varotsos, Alexopoulos, and
Nomikos initiated in 1980’s.
Based on multi-dipole DC-electric field observation
Anomaly (SES) appears before the impending sizable
earthquake (EQ).
They claimed that they predicted M≥5 Greek EQs.
The criteria for successful prediction are: < a few
weeks in time, <0.7 units in magnitude (M, hereafter),
and <100 km in epicentral distance. The length of
time window depends on the type of signals (a few
days to months).
Recognition of the VAN method
Generally, not well recognized among the
seismological community
 A lot of debates/counterarguments

Recent EOS articles
Geophys. Res. Lett. 23 (debates of VAN)

VAN group’s way of writing is not reader
oriented (difficult to understand)
On going forecast!
http://arxiv.org/abs/0904.2465
Cornell University website http://arxiv.org/abs/0904.2465
The same holds for a non-dichotomous signals
on March 28, 2009 at Keratea station located
close to Athens (Fig. 8)
To approach the occurrence time of the impending
event, the procedure developed in Ref 32 has been
employed for the seismicity within are N37.738.8, E22.6-24.1.
Natural Time Analysis

P. A. Varotsos and his group

Natural Time Analysis is effective to
predict a critical point in the timeseries of critical phenomena.
– Large earthquakes
• Varotsos et al., Phys. Rev. E,
2002, 2003, 2006, 2007
– Phase transition on 2D Ising spin systems
• Varotsos et al., Phys. Rev. E, 2003
– Heart attack
• Varotsos et al., Phys. Rev. E,
2004, 2005
(New Scientist)
Natural Time
k : k th event
N : total number of events
(Varotsos, Is time continuous ?, submitted to Phys. Rev. Lett., 2008)
Self-organized Criticality
Plate motion
Is EQ SOC phenomenon ?
EQs
(Sand pile model)
Bak et al., Phys. Rev. Lett. (1987)
Bak & Tang J. Geophys. Res. (1989)
Critical phenomena -> SOC o
SOC -> Critical phenomena X
Critical point
Critical point
(Long range correlation)
Triggering ?
Large EQ
One Case (Conventional Time)
Divorce
Energy
Critical Point
Extramarital affair
First Fight
Second affair
Fight
Fight
Conventional Time
Another Case (Conventional Time)
Divorce
Energy
Critical Point
Extramarital affair
Second affair
First Fight
Fight
Fight
Conventional Time
Energy
Similar Shape
0
Natural Time
1
Power spectrum
Qxk : Seismic Moment
ω
: Natural frequency
Power spectrum at Critical Point ?
Candidate of Critical Point
Coincidence
Time series of
Coincidence
Coincidence
True Coincidence
Coincidence
Scale invariance
(Magnitude and Area)
True Coincidence
2000 Izu Swarm EQs
(Uyeda, Kamogawa & Tanaka, JGR, 2009)
Time-series of power spectrum
Time series of k1
Candidate of
True Coincidence
Tentative




conclusion
EM phenomena may reflect critical state of the crust
(at least Greek group claims that SES is a critical
phenomenon)
EM phenomena are not statistical but deterministic
ones
Combination of multi-parameter monitoring is
essentially important
If EQs are critical phenomena, Natural Time analysis
may connect seismicity and SES activity (EM
phenomena)
Future Plans





Proceed RTL algorism research with Prof. Huang
(Peking University)
Proceed Natural Time analysis
Proceed cooperation with Keilis-Borok group
To solve fundamental problem of EM phenomena
related to EQs
EM signal generation and transmission
To proceed LAI (lithosphere-Atmosphere and
Ionosphere) coupling study
-> to merge mechanical process and EM phenomena
Both Seismic activity and Ionosphere are
really near earth surface matter !
Preseismic LAI coupling
Kamogawa (2006)
References


Fraser-Smith et al., Low-frequency magnetic field measurements near the
epicenter of the Ms 7.1 Loma Prieta earthquake, Geophys. Res. Lett., 17,
1465-1468, 1990.
Nagao et al., Electromagnetic anomalies associated with 1995 KOBE
earthquake, J. Geodynamics, 33, 401-411, 2002.
For Natural Time
 SARLIS et al., Investigation of seismicity after the initiation of a Seismic
Electric Signal activity until the main shock, Proceedings of the Japan
Academy, Series B, Vol. 84 , No. 8, 331-343, 2008.
 Varotsos, The Physics of Seismic Electric Signals, TerraPub, Tokyo, Japan, 338
pp., 2005.
 Uyeda et al., Analysis of electrical activity and seismicity in the natural time
domain for the volcanic-seismic swarm activity in 2000 in the Izu Island
region, Japan, JGR, 114, B02310, doi:10.1029/2007JB005332, 2009.
For LAI coupling
 Kamogawa, M., Preseismic Lithosphere-Atmosphere-Ionosphere Coupling,
EOS, Vol. 87, Num. 40, 417, 424, 2006.

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