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Tokyo

Nagoya

Earthquake Prediction Research Center, Tokai University

Toshiyasu NAGAO

Combined approach using the electromagnetic precursory phenomena and critical phenomena for a

short-term earthquake prediction

Today’s talk What is “Seismo-Electromagnetics”

some examples (California and Japan) Greek VAN method Introduction of Natural Time analysis Introduction of LAI (Lithosphere-Atmosp

here 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 (Fraser-Smith et al., 1990)

However………　 We know that 　　－＞　 EM phenomena preceded by EQs are so small !

M7.1 Loma Prieta (California) EQ in 1989

Seismo-Electromagnetics in Japan

100Ｍ

10Ｍ

1Ｍ

100ｋ

10ｋ

1ｋ

100

10

1

0.1

ＤＣ

（Ｈｚ）

ＵＬＦ

ＶＨＦ

ＨＦ

ＭＦ

ＬＦ

ＶＬＦ

ＥＬＦ

telluric current

3-comp. magnetic

Narrow band 3-comp. magnetic2-comp. magnetic for direction findingEM pulse measurements in a boreholeAnomalous transmission of radio waves

Natural noise observation

Blue letters　 Ionosphere/troposphere anomaly　 (radio wave transmission anomaly)

Brown letters Signals emitted from the lithosphere

Micro wave observation

Vertical E-field measurements in a borehole

FM broadcast wave anomalous transmission

Nagao et al., 2002(J. Geodynamics)

Seismo-Electromagnetic studies in Japan

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.)

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)

Signals emitted from the lithosphere

Ionosphere/troposphere anomaly

Izu 2000 events (volcanic eruption and intense seismic activity)

3-comp. magnetometer array

Izu 1998-2000

1998 1999 2000

E-field Niijima (0.01Hz)

Eigenvalue (λ3, 0.1Hz)Izu Pen.3-comp. Mag array.

Activity started

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. Th

e 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 orie

nted (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 locatedclose to Athens (Fig. 8)To approach the occurrence time of the impendingevent, the procedure developed in Ref 32 has beenemployed for the seismicity within are N37.7-38.8, 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 time-series 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

(Varotsos, Is time continuous ?, submitted to Phys. Rev. Lett., 2008)

k : k th event

N : total number of events

Self-organized Criticality

(Sand pile model)

Bak et al., Phys. Rev. Lett. (1987)Bak & Tang J. Geophys. Res. (1989)

Is EQ SOC phenomenon ?

Plate motion

EQs Critical phenomena -> SOC oSOC -> Critical phenomena X

Critical point

Critical point(Long range correlation)

Triggering ?

Large EQ

One Case (Conventional Time)

En

erg

y

Fight

Extramarital affair

Divorce

First FightSecond affair

Fight

Critical Point

Conventional Time

Another Case (Conventional Time)

Conventional Time

En

erg

y

Fight

First Fight

Fight

Critical Point

Extramarital affair

Second affair

Divorce

Similar ShapeEn

erg

y

Natural Time0 1

Power spectrum

: Natural frequency

: Seismic Moment

Power spectrum at Critical Point ?

Qxk

ω

Candidate of Critical Point

Coincidence

Time series of

Coincidence Coincidence

True Coincidence

Scale invariance(Magnitude and Area)

Coincidence

True Coincidence

2000 Izu Swarm EQs(Uyeda, Kamogawa & Tanaka, JGR, 2009)

Time-series of power spectrum

Time series of k1

Candidate ofTrue Coincidence

Tentative conclusion EM phenomena may reflect critical state of the crust (a

t 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 (Pe

king University) Proceed Natural Time analysis Proceed cooperation with Keilis-Borok group To solve fundamental problem of EM phenomena rel

ated to EQs EM signal generation and transmission To proceed LAI (lithosphere-Atmosphere and Ionosp

here) 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 epic

enter 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 Elec

tric 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, E

OS, Vol. 87, Num. 40, 417, 424, 2006.