europlanet graz, 1-2 june 2007 1 gerald duma central institute for meteorology and geodynamics...
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1
Europlanet Graz, 1-2 June 2007
Gerald Duma
Central Institute for Meteorology and Geodynamics
Vienna, Austria
AN ELECTROMAGNETIC PROCESS REGULATES EARTHQUAKE
ACTIVITY
WorkshopEarthquakes: Ground-based and Space Observations
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Europlanet Graz, 1-2 June 2007
Studies performed
10-year research pogramme Several cooperations in Europe, Asia, America Effect verified for many earthquake zones worldwide Plausible interpretation and model
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Europlanet Graz, 1-2 June 2007
Observations (1996) – daily range
AUSTRIAM 2.5, 1901-1990
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (UTC +1)
02
04
06
0
Nu
mb
er
of
ea
rth
qu
ake
s /
ho
ur
(3 h
r ru
nn
.av.
)
20
77
02
07
80
20
79
02
08
00
Ma
gn
etic
inte
nsi
ty (
nT
)
Sq-variationObs W IK, 1983-85
comp N
GeomagneticObservatory
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Europlanet Graz, 1-2 June 2007
Duma, Vilardo (INGV),1998
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC +1)
01
00
20
03
00
40
0
Str
ain
re
lea
se /
ho
ur
(3 h
r ru
nn
.av.
)
24
39
02
44
00
24
41
02
44
20
Ma
gn
etic
inte
nsi
ty (
nT
)
Sq-variationObs AQU, 1986
comp N
GeomagneticObservatory
Observations (1997) – daily range
Mt. VESUVIUS volcanic eqs, area 10 x 10 km , 1.8 M 3.1,
1972-1996, 1400 events
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Europlanet Graz, 1-2 June 2007
A seismic daily cycle
Aristoteles Pliny the Elder, 79 A.D. eruption of Mt.Vesuvius Tams, 1926 Conrad, 1932 Shimshoni, 1972 Lipovics, 2000, 2005 Schekotov & Molchanov, 2005 Poorly investigated in recent decades, no
interpretation given yet
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Europlanet Graz, 1-2 June 2007
A seismic daily cycle
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (M EZ)
04
81
21
62
0
04
81
21
62
0
04
81
21
62
0
Num
ber
of e
arth
quak
es p
er h
r (3
-hrs
run
n.av
.)
1901-1930
1961-1990
1931-1960
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (M EZ)
020
4060
Num
ber
of e
qs p
er
hr
04
812
entireAUSTRIA1901-1990
IMST1997
3 sub-periods 20th centuryAUSTRIAM 2.5
May 31 – June 18, 1997Earthquake swarm in Austria,
region IMST
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Europlanet Graz, 1-2 June 2007
A seismic daily cycle
Observed in many main seismic regions
Earthquakes M 5 and M 6
A very powerful geodynamic process acting!
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Europlanet Graz, 1-2 June 2007
GeomagneticObservatory
1880 1900 1920 1940 1960 1980 2000Year
02
46
8
Num
ber
of e
arth
quak
es p
er y
ear
(10
yr r
unn.
av.)
2040
020
650
2090
0
Mag
netic
inte
nsity
(nT
)
Obs WIK, comp N
‚ secular variation‘
AUSTRIAM 3.1 (Io 5°)
Observations (1996) – long term
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Europlanet Graz, 1-2 June 2007
Mechanism, models?
Dependence on Local Time Process related to sun A mechanism which penetrates the whole Earth‘s lithosphere Tides ? No! High energy mechanism
Can a few nT influence tectonic performance?
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
Geomagnetic variations in a conductive lithosphere
Maxwell‘s equations (E-H) ‚Telluric currents‘ associated with all natural
geomagnetic variations (frequency range from min – solar cycle)
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
Telluric currents and forces
F = e . [ ve . B ]
F ... mechanic force vector
e ... electron charge
ve ... velocity vector
B ... magnetic field vector
‚Lorentz force‘
F
B
ve
e
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
Magnetic observatories monitor: H(t) ~ IH(t) ~ FV(t) vertical force
M agneticO bservatory
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
R up ture zone
r
P1
P2
I2 ≠ I1
Regional mechanic moment, torque Tr
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
The gradient of H(t) reflects the change of regional torque Tr(t) (azimuth Az)
G eogr. Longitude
Geo
gr. L
atitu
de
Seism ic reg ionH(Long,Lat)
grad
ient
H
(directio
n A
z)Torque
axis
P
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Europlanet Graz, 1-2 June 2007
Energy – diurnal variation
T = MM x H
MMMagnetic Moment
I
Horizontal intensity HEarth’s main field
Ionospheric current system
Lithospheric current systeminduced
A large scale current field, covering 1/3 of the
northern Earth‘s hemisphere
The dayside Sq induced lithospheric current vortex (Chapman, Bartels, 1940; Matsushita, 1968)
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Europlanet Graz, 1-2 June 2007
Energy – diurnal variation
The mechanic moment of Sq for a single loop (Duma, Ruzhin, 2003)
Vsm2Am 11100.89
4)/(DIMM
A 10 10 I current Ring
km 3000 D Diameter
: MM moment Magnetic
0
2
3
Joule VAs 10 26.6 A/m 30 *Vsm )10.(
HMM T
:TTorque
11
11
890
The example demonstrates:
The deformation energy provided to the lithosphere by a single current loop, radius 1500 km and current 10 kA, is equivalent to the energy of an earthquake M 5,1.
50
0
10 kA
1500 km
1000( ca . 1 h r LT )
resistivity:5 * 102 ohmm
current density:2 * 10-8 A/m2
M M ’
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Europlanet Graz, 1-2 June 2007
Energy – diurnal variation
60% of total moment concentrates in a 30° segment
0
0
0
0
0
0
0.1
0.1
0.1
0.2
0
0
0
0
0
0
0.1
0.1
0.1
0.2
0
0
0
0
0
0.1
0.1
0.1
0.2
0.2
0
0
0
0
0
0.1
0.1
0.1
0.2
0.2
0
0
0
0
0
0.1
0.1
0.1
0.2
0.3
0
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0
0
0
0
0.1
0.1
0.1
0.2
0.3
0.4
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0.4
0
0
0
0
0.1
0.1
0.2
0.3
0.3
0.4
0
0
0
0
0.1
0.1
0.2
0.3
0.4
0.5
0
0
0
0.1
0.1
0.2
0.2
0.3
0.4
0.6
0
0
0
0.1
0.1
0.2
0.3
0.4
0.5
0.6
0
0
0
0.1
0.1
0.2
0.3
0.4
0.6
0.7
0
0
0
0.1
0.2
0.2
0.4
0.5
0.7
0.8
0
0
0
0.1
0.2
0.3
0.4
0.6
0.8
1
0
0
0.1
0.1
0.2
0.3
0.5
0.7
0.9
1.1
0
0
0.1
0.1
0.3
0.4
0.6
0.8
1
1.3
0
0
0.1
0.2
0.3
0.5
0.7
1
1.2
1.5
0
0
0.1
0.2
0.4
0.6
0.9
1.1
1.4
1.7
0
0
0.1
0.3
0.5
0.8
1.1
1.4
1.7
2
0
0.1
0.2
0.4
0.6
1
1.3
1.6
2
2.3
0
0.1
0.2
0.5
0.8
1.2
1.6
2
2.3
2.6
0
0.1
0.3
0.7
1.1
1.5
2
2.4
2.7
3.1
0
0.2
0.5
1
1.5
2
2.4
2.8
3.2
3.5
0
0.3
0.8
1.4
2
2.5
3
3.4
3.7
4
0.1
0.5
1.2
2
2.6
3.2
3.6
4
4.2
4.4
0.2
1
2
2.8
3.5
4
4.3
4.6
4.7
4.9
0.5
2
3.2
4
4.4
4.7
4.9
5.1
5.2
5.2
2
4
4.7
5.1
5.2
5.3
5.4
5.4
5.4
5.5
5.5
5.5
5.5
5.5
5.5
5.5
5.5
5.5
5.5
5.5
2
4
4.7
5.1
5.2
5.3
5.4
5.4
5.4
5.5
0.5
2
3.2
4
4.4
4.7
4.9
5.1
5.2
5.2
0.2
1
2
2.8
3.5
4
4.3
4.6
4.7
4.9
0.1
0.5
1.2
2
2.6
3.2
3.6
4
4.2
4.4
0
0.3
0.8
1.4
2
2.5
3
3.4
3.7
4
0
0.2
0.5
1
1.5
2
2.4
2.8
3.2
3.5
0
0.1
0.3
0.7
1.1
1.5
2
2.4
2.7
3.1
0
0.1
0.2
0.5
0.8
1.2
1.6
2
2.3
2.6
0
0.1
0.2
0.4
0.6
1
1.3
1.6
2
2.3
0
0
0.1
0.3
0.5
0.8
1.1
1.4
1.7
2
0
0
0.1
0.2
0.4
0.6
0.9
1.1
1.4
1.7
0
0
0.1
0.2
0.3
0.5
0.7
1
1.2
1.5
0
0
0.1
0.1
0.3
0.4
0.6
0.8
1
1.3
0
0
0.1
0.1
0.2
0.3
0.5
0.7
0.9
1.1
0
0
0
0.1
0.2
0.3
0.4
0.6
0.8
1
0
0
0
0.1
0.2
0.2
0.4
0.5
0.7
0.8
0
0
0
0.1
0.1
0.2
0.3
0.4
0.6
0.7
0
0
0
0.1
0.1
0.2
0.3
0.4
0.5
0.6
0
0
0
0.1
0.1
0.2
0.2
0.3
0.4
0.6
0
0
0
0
0.1
0.1
0.2
0.3
0.4
0.5
0
0
0
0
0.1
0.1
0.2
0.3
0.3
0.4
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0.4
0
0
0
0
0.1
0.1
0.1
0.2
0.3
0.4
0
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0
0
0
0
0
0.1
0.1
0.2
0.2
0.3
0
0
0
0
0
0.1
0.1
0.1
0.2
0.3
0
0
0
0
0
0.1
0.1
0.1
0.2
0.2
0
0
0
0
0
0.1
0.1
0.1
0.2
0.2
0
0
0
0
0
0
0.1
0.1
0.1
0.2
0
0
0
0
0
0
0.1
0.1
0.1
0.2
-8000 -6000 -4000 -2000 0 2000 4000 6000 8000
1000
2000
km 30
40
50
20
10
0
Geographic latitude
60
Local Time
6 9 12 15 18
H
I
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Europlanet Graz, 1-2 June 2007
Modelling the electromagnetic effect
Data for H(lat,long) to compute gradient
Daily variation: hourly mean values
Model of Sq telluric current vortex Regional observatory data (lati, longi)
Long term: annual mean values
Retrieved from IGRF, 1900-2010 (grid data) Regional observatory data (lati, longi)
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Europlanet Graz, 1-2 June 2007
Case studies – Regions
Austria Taiwan
California Baikal region
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Europlanet Graz, 1-2 June 2007
Case studies – Austria (M ≥ 3.2, Gradient H – N10W)
Gradient H from IGRF10 (1900-2010)
Diurnal range Long term
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 1)
11.
21.
41.
61.
82
Mod
el M
SM
- T
OR
QU
E T
(log
ener
gy, r
elat
ive)
-0.0
8-0
.04
00
.04
0.08
log
sei
smic
ene
rgy
/ hou
r(3
-hr
runn
.av.
)
1900 - 2003
1920 1940 1960 1980 2000Y ear
-2.0
-1.8
-1.6
-1.4
-1.2
-1.0
log
sei
smic
ene
rgy
/ yea
r(1
1-yr
run
n.av
.)
0.0
0.2
0.4
0.6
Mod
el M
SM
- T
OR
QU
E T
(log
ener
gy, r
elat
ive)
Gradient H from Sq-Model
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Europlanet Graz, 1-2 June 2007
Case studies – Taiwan (M ≥ 5, Gradient H – N55E)
Gradient H from IGRF10 (1900-2010)
Diurnal range Long term
Gradient H from Sq-Model
1973 - 1998
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (UTC +8)
1.2
1.4
1.6
1.8
22
.2
Mod
el M
SM
- T
OR
QU
E T
(log
ener
gy, r
elat
ive)
0.2
40
.26
0.2
80
.30
.32
0.3
4
log
seis
mic
ene
rgy
/ hou
r(3
-hr
runn
.av.
)
1970 1980 1990 2000 2010
0.0
0.4
0.8
1.2
log
en
erg
y re
lea
se /
yea
r(5
-yrs
ru
nn
.av.
)
00.
40
.81.
2
Mod
el M
SM
- T
OR
QU
E
(ene
rgy,
rel
ativ
e)
Chi-Chi, 1999
22
Europlanet Graz, 1-2 June 2007
Case studies – Baikal area (M ≥ 5, Gradient H – N00E)
Gradient H from IGRF10 (1900-2010)
Diurnal range Long term
Gradient H from Sq-Model
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
log
sei
smic
ene
rgy
/ ye
ar(5
-yr
run
n.a
v.)
-4-2
02
Mo
de
l MS
M -
TO
RQ
UE
T(l
og
en
erg
y, r
ela
tive
)
1900 1920 1940 1960 1980 2000Y ear
eq-cata logue:U SG S(PD E)
eq-cata logue:SSR
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC -7)
1.2
1.4
1.6
1.8
2
Mo
del
MS
M -
TO
RQ
UE
T(l
og
en
erg
y, r
ela
tive
)
-0.1
00
.10
.20
.3
log
se
ism
ic e
ne
rgy
/ ho
ur
(5-h
r ru
nn
.av.
)
eq-cata logue:U SG S(PD E)(2001-2006)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC -7)
0.8
11.
21.
41.
61.
82
Mo
del
MS
M -
TO
RQ
UE
T(l
og
en
erg
y, r
ela
tive
)
0.2
0.25
0.3
0.35
0.4
0.45
log
sei
smic
ene
rgy
/ ho
ur
(5-h
r ru
nn.a
v.)
eq-cata logue:SSR (1900-1980)
1900 - 1980
2001 - 2006
23
Europlanet Graz, 1-2 June 2007
Case studies – California (M ≥ 6, Gradient H – N30E)
Gradient H from IGRF10 (1900-2010)
Diurnal range Long term
Gradient H from Sq-Model
1970 - 2005
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC -8) 1
.82
. 02
. 22
.42
.6
Mod
el M
SM
- T
OR
QU
E T
(lo
g en
ergy
, rel
ativ
e)
0.2
0.2
40
.28
0.3
20
.36
log
seis
mic
en
erg
y / h
our
(3-h
r ru
nn.
av.
)
1890 1910 1930 1950 1970 1990 2010Y ear-0
.8-0
.40.
00.
40.
8
log
se
ism
ic e
ne
rgy
/ ye
ar
(9 y
ea
r m
ov.
av.
)
-2.5
-2-1
.5-1
-0.5
00.
5
Mo
de
l SM
S -
TO
RQ
UE
T(l
og
en
erg
y, r
ela
tive
)
24
Europlanet Graz, 1-2 June 2007
Case study – earthquakes 2004-2006 2004 08 01 – 2006 12 31, M 5
S-ITALYIONIAN IS
AEGEAN
25
Europlanet Graz, 1-2 June 2007
Case study – earthquakes 2004-2006
IONIAN ISLANDSSeismic activity – Local Time
M 5
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 2)
-0.1
-0.05
0
0.05
0.1
0.15
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 2)
-0 .4
-0.3
-0.2
-0.1
0
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
1965 – 1989 (25 yrs, PDE)
1990 – 2003 (14 yrs, PDE)
2004 08 01 – 2006 12 31 M 5
n = 11 (PDE)
Gradient H (N85E)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 2)
-50
-25
0
25
50
Mod
el M
SM
- T
OR
QU
E(lo
g en
ergy
, rel
ativ
e)
-0.2
-0.1
0
0.1
en
erg
y re
lea
se /
ho
ur
(ru
nn
. av.
)
26
Europlanet Graz, 1-2 June 2007
Case study – earthquakes 2004-2006 1910 – 1980 (72 yrs, INGV)
2004 08 01 – 2006 12 31 M 5n = 4 (PDE)
2004 08 01 – 2006 12 31 M 4.5 n = 11 (PDE)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 1)
-0 .5
-0.4
-0.3
-0.2
-0.1
0
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 1)
-0 .2
-0.1
0
0.1
0.2
0.3
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 1)-0 .4
-0.3
-0.2
-0.1
0e
ne
rgy
rele
ase
pe
r h
ou
r (l
og
)(r
un
n.a
v.)
S-ITALYSeismic activity – Local Time
M 5
27
Europlanet Graz, 1-2 June 2007
Case study – earthquakes 2004-2006
Aegean Sea
2004 08 01 – 2006 12 31 M 5n = 5 (PDE)
Crete
Aegean Sea vs. CreteSeismic activity – Local Time
M 5
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 2)-0 .3
-0.2
-0.1
0
0.1
0.2
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
2004 08 01 – 2006 12 31 M 5n = 4 (PDE)
0 2 4 6 8 10 12 14 16 18 20 22 24Local T im e (U TC + 2)
-0 .3
-0.2
-0.1
0
0.1
0.2
en
erg
y re
lea
se p
er
ho
ur
(lo
g)
(ru
nn
.av.
)
Aegean Sea / Strongest events 2004-2006:
2006 01 08 UT=11 34 55.64 lat=36.31° long=23.21° d=66 km M=6.7
28
Europlanet Graz, 1-2 June 2007
Case study – earthquakes 1963-2006
AegeanM 4, n = 956 (NOA)
1960 1970 1980 1990 2000 2010
010
203
040
50
Ann
ual n
umbe
r of
eqs
(5 y
r m
ov.a
v.)
-0.8
-0.4
00.4
0.8
Mod
el M
SM
- T
OR
QU
E T
(log
ener
gy, r
elat
ive)
1960 1970 1980 1990 2000 2010
04
81
21
6
Ann
ual n
umbe
r of
eqs
(5 y
r m
ov.a
v.)
Ionian IsM 4, n = 237 (NOA)
Gradient H from IGRF10
AEGEAN vs. IONIAN ISSeismic activity – long term
M 4
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Europlanet Graz, 1-2 June 2007
Case study – earthquakes 1963-2006
Ionian IsM 5, n = 36 (NOA)
S-ItalyM 5, n = 57 (INGV+PDE)
1960 1970 1980 1990 2000 2010
-1.5
-1-0
.50
0.5
1
log
ener
gy r
elea
se /
year
(5 y
r m
ov.a
v.)
1960 1970 1980 1990 2000 2010
-1.5
-1.0
-0.5
0.0
log
ener
gy r
elea
se /
year
(5 y
r m
ov.a
v.)
S-ITALY vs. IONIAN ISSeismic activity – long term
M 5
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Europlanet Graz, 1-2 June 2007
Novel aspects
External sources – causing geomagnetic variations - strongly influence seismic activity (trigger)
Origins: solar radiation, ionosphere, Sq ; magnetic dynamo
Answer to daily rhythm of seismic activity (LT) Monitoring the process: easy by geomagnetic
observatories Predictability: systematic diurnal, seasonal, secular
variations (IGRF 2010) Not yet investigated: influence of magnetic storms Faster monitoring of variations by space observations ?
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Europlanet Graz, 1-2 June 2007
Observations (1997) – long term
Duma, Vilardo (INGV),1998
n: annual number of eqs M 1.8, 1972-1996sf: annual number of solar flares (103)
Duma, Vilardo (INGV),1998
sf
n
1960 1970 1980 1990 2000Year
04
81
2
An
nu
al n
um
ber
of
sola
r fl
ares
(10
3 )
01
00
20
03
00
40
0
An
nu
al n
um
ber
of
eqs
(5 y
r ru
nn
.av.
)
Solar cyclesNo. 20 No. 21 No. 22
Mt. VESUVIUS volcanic eqs, area 10 x 10 km , 1.8 M 3.1,
1972-1996, 1400 events
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Europlanet Graz, 1-2 June 2007
Tectonic settings & faulting mechanisms in Greece
(Dewey et al., 1973 / A. Tzanis, UOA, 2003)
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Europlanet Graz, 1-2 June 2007
Model of Sq telluric current vortex Fits observed Sq-variations at observatories Computes grad H(LT)
Seism icregion
Sq inducedcurrent vortex
M
P
Q
P
North
East
Surface at P
Seismic region
Curr - E
Cur
r - N
Current I
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Europlanet Graz, 1-2 June 2007
H – current density
293
6
6
30
/10310
103
/3/103
10;24;10;2
mAE
j
kmmVmVE
mhTnTHTH
E
y
x
y
x
:example) space (half theory neticElectromag
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Europlanet Graz, 1-2 June 2007
The electromagnetic model
M agneticO bservatory
Magnetic observatories monitor horizontal force FhC (t)
Z
Earth’s m ainm agnetic field
H
C
G eogr.North time
C
H or . F or ce
F h [I x Z]
CC
Ccu rr. IC
Z
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Europlanet Graz, 1-2 June 2007
Energy – diurnal variation Sq: solar controlled, heating, ionization, tides
(Chapman, Bartels, 1940)
Ionospheric current system (Chapm an, Barte ls, 1940)dayside vortex, N -hemisphere
currents in 1000 Am pere
rot.
10 LT8 LT
6 LT