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Analisi statistica della correlazione
tra livello dell'acqua di invasi idrici e
sismicita' indotta
Luciano Telesca
Institute of Methodologies for Environmental Analysis
National Research Council, Italy
e-mail: luciano.telesca@imaa.cnr.it
1. Koyna-Warna (India)
2. Açu (Brazil)
3. Aswan (Egypt)
4. Enguri (Georgia)
Case studies
1. Koyna-Warna (India)
(Gupta et al., BSSA, 1980)
•Dam is 103 m high
•Previously a low-sesmicity area
•Impounding of water began in 1962
•Reports of local EQs increased dramatically
•Seismograms showed foci concentrated at
shallow depths under Shivajisagar Lake
•M 6.5 EQ close to the Dam on Dec. 10, 1967
Telesca, BSSA, 2317-2312, 2010
-200 0 200 400 600 800 1000 1200 1400
2.0
2.5
3.0
3.5
4.0
4.5
ma
gn
itu
de
days since January 1, 20010 200 400 600 800 1000 1200
0
5
10
cba
4321
Ndays since January 1, 2001
630
640
650
660
W (
m)
1. Koyna-Warna (India)
Observation period: 2001-2004
Mc =2.2
B-value=1.3
-300 -200 -100 0 100 200 300
-0.10
-0.05
0.00
0.05
0.10
0.15237 d
cro
ss-c
orr
ela
tio
n b
etw
ee
n n
an
d w
time lag (day)
-300 -200 -100 0 100 200 300
-0.10
-0.05
0.00
0.05
0.10
0.15
cro
ss-c
orr
ela
tio
n b
etw
ee
n n
an
d w
time lag (day)
Telesca, BSSA, 2317-2312, 2010
1. Koyna-Warna (India)
99%
Confidence curve at 99%
Saar and Manga, Earth Planet. Sci. Lett. 214, 605–618, 2003 Little, et al., J. Acoust. Soc. Am., 119, 546–558, 2006
Telesca, BSSA, 2317-2312, 2010
10-3
10-2
10-1
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
4 mo1/2 y1 y
fc=0.0088
99%
Pw(f
)
f (1/day)
10-3
10-2
10-1
10-7
10-6
10-5
10-4
10-3
10-2
fc=0.005
40 d2 mo
99%
Pn(f
)
f(1/day)
-200 0 200 400 600 800 1000 1200 1400
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
wS, n
S
days since January 1, 2001
wS
nS
1. Koyna-Warna (India)
Telesca, BSSA, 2317-2312, 2010
-300 -200 -100 0 100 200 300
-0.4
-0.2
0.0
0.2
0.4
0.6 223 d
99%
cro
ss-c
orr
ela
tio
n b
etw
een
nS a
nd
wS
time lag (day)
-300 -200 -100 0 100 200 300
-0.4
-0.2
0.0
0.2
0.4
0.6237 d
99%
cro
ss-c
orr
ela
tion b
etw
een n
S2 a
nd w
S2
time lag (day)
subperiod 1
-300 -200 -100 0 100 200 300
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
228 d
cro
ss-c
orr
ela
tio
n b
etw
een
nS
2 a
nd
wS
2
time lag (day)
subperiod 2
1. Koyna-Warna (India)
Telesca, BSSA, 2317-2312, 2010
Hydrological model
tiePhtPt
P
h
PD
02
2
)0,(,
D
hti
Dh
eeP
P
22
0
Diffusion equation and
boundary conditions
Solution
D: Hydraulic diffusivity
P: Pore pressure
H: depth
Plane wave:
1. attenuation coefficient
2. velocity
D2
D2
Decrease of the pore-pressure amplitude with depth h
Periodic behavior of the pressure as a function of depth h and time t
1. Koyna-Warna (India)
Telesca, BSSA, 2317-2312, 2010
Hydrological model
2
2
2 t
hD
Diffusivity
=2(year)-1
t=223 days
h= mean depth h of the seismic events
D=0.200.18 m2/s
1. Koyna-Warna (India)
Telesca, do Nascimento, Bezerra, Ferreira, NHESS, 12, 805, 2012
Telesca, do Nascimento, Bezerra, Ferreira, in preparation, 2013
2. Açu (Brazil)
0
20
40
60
80
0 20 40 60 80 100 120 14024
26
28
30
32
34
months since 1987
W
water monthly EQ counts
N
Period: Jan 1987-Mar 1997
0.0 0.1 0.2 0.3 0.4 0.5
0.00
0.05
0.10
0.15
0.20
0.25
99%
1 y
Pw
f(1/month)
water level
0.0 0.1 0.2 0.3 0.4 0.5
0.02
0.04
0.06
0.08
0.10
99%
1 y
Pn
f(1/month)
EQ monthly count
0.0 0.1 0.2 0.3 0.4 0.5
0.00
0.05
0.10
0.15
0.20
0.25
Pw, P
n
f(1/mo)
water
EQ
1 y
Power
spectrum
analysis
2. Açu (Brazil)
Telesca, do Nascimento, Bezerra, Ferreira, in preparation, 2013
40 50 60 70 80 90 100 110 120
-6
-4
-2
0
2
4
6
months since 1987
tim
e la
g (
mo
nth
)
0.3600
0.3900
0.4200
0.4500
0.4800
0.5100
0.5400
0.5700
0.6000
40 50 60 70 80 90 100 110 120
-6
-4
-2
0
2
4
6
months since 1987
tim
e la
g (
mo
nth
)
-0.5000
-0.3625
-0.2250
-0.08750
0.05000
0.1875
0.3250
0.4625
0.6000
Cross-correlation analysis time variation of the cross-correlation: time window of 36 months
shifting by 1 month through the overall record; the data included
within such time window were cross-correlated and the results
associated to the time of the last datum in the window
b d
a
c
2. Açu (Brazil)
Telesca, do Nascimento, Bezerra, Ferreira, in preparation, 2013
3. Aswan (Egypt)
1981 Aswan Eq occurred 17 years after the starting of reservoir filling
•Temporal variations of shallow seismicity associated with a high rate of water level fluctuation, while no clear correlation with the deeper seismicity (Awad and Mizoue, 1995) •Maximum correlation at timelag of 2 months during 1982–1985 (depth h< 40 km, M> 2.0) (Selim et al. 2002)
•Seismicity rate correlates with the seasonal fluctuations of the lake level, indicating positive evidence for the Aswan seismicity to be reservoir-triggered in the 1982–2001 (Mekkawi et al., 2004)
3. Aswan (Egypt)
Telesca, Mohamed, ElGabry, El-Hady , Elenean, Chaos Solitons & Fractals, 45, 47, 2012
Telesca, Lovallo, Mohamed, ElGabry, El-Hady, Elenean, ElBary, Physica A, 391, 2889, 2012
Telesca, Lovallo, Mohamed, ElGabry, El-Hady, Elenean, ElBary, NHESS, 12, 1267, 2012
Telesca, ElBary, Mohamed, ElGabry, NHESS, 12, 2203, 2012
Analysed period: 1 Jan 1982 to 31 Dec 2010
Data Source: Bulletins of the Aswan Earthquake Regional Research Center
Size of the whole catalogue: 7901
Size of the catalogue after declusterization (Reasenberg (1985)): 3545
Mc=2.5
3. Aswan (Egypt)
Telesca, ElBary, Mohamed, ElGabry, NHESS, 12, 2203, 2012
3. Aswan (Egypt)
Telesca, ElBary, Mohamed, ElGabry, NHESS, 12, 2203, 2012
3. Aswan (Egypt)
Telesca, ElBary, Mohamed, ElGabry, NHESS, 12, 2203, 2012
Time-variant cross-correlation: time window of 6 years, moving through the data, with a shift of 1 month
4. Enguri (Georgia)
0 2 4
100
101
102
103
Threshold magnitude
Cu
mu
lati
ve
Nu
mb
er
Mc
Telesca, Matcharashvili, Chelidze, NHESS, 12, 1905, 2012
•Heigth: 272 m
•Building period: 1971-1983 • Preliminary flooding of the territory started at the end of December 1977
•Period of analysis: 1978-2010 •Size of declustered catalogue: 2131
•Max mag: 4.7 •Depth max: 32 km •Mc: 1.6 •b-value: 0.92 (whole Caucasus 0.72)
0 100 200 300 400
320
340
360
380
400
420
440
460
480
500
520
0
10
20
30
40
50
m
months since April 1978
water level
2
1
b
a
EQ number
N
10-3
10-2
10-1
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
a)
water level 1 y
w=1.77+0.10
P(f
)
f (1/month)
10-3
10-2
10-1
10-6
10-5
10-4
10-3
10-2
10-1
100
101
seismicity
b)
s=0.60+0.10
P(f
)
f (1/month)
4. Enguri (Georgia)
Telesca, Matcharashvili, Chelidze, Zhukova, NHESS, 12, 2479, 2012
0 5 10
0
10
20
30
40
50
60
70
va
ria
nce
of e
ach
co
mp
on
en
t (%
of th
e to
tal)
order
seismicity
water level
0 100 200 300 400
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
a)
V
r1
0 100 200 300 400
-2
0
e)
water level r1
0 100 200 300 400
-0.4
-0.2
0.0
0.2
0.4
0.6
b)
V
r2
0 100 200 300 400
0
f)
r2
0 100 200 300 400
0
c)
V
r3
0 100 200 300 400
0
g)
r3
0 100 200 300 400
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
d)
seismicity
V
t (month)
r4
0 100 200 300 400
-0.3
-0.2
-0.1
0.0
0.1
0.2
0.3
h)
t (month)
r4
4. Enguri (Georgia)
Telesca, Matcharashvili, Chelidze, Zhukova, NHESS, 12, 2479, 2012
Singular spectrum analysis
10-3
10-2
10-1
10-6
10-5
10-4
10-3
10-2
10-1
100
101
2.09+0.03
a)
water levelseismicity
P(f
)
r1
10-3
10-2
10-1
10-4
10-3
10-2
10-1
1.87+0.02
e)
r1
10-3
10-2
10-1
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
1 y
1 y
b)
P(f
)
r2
10-3
10-2
10-1
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
1 y
1 y
f)
r2
10-3
10-2
10-1
10-5
10-4
10-3
10-2
10-1
c)
P(f
)
r3
10-3
10-2
10-1
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
g)
r3
10-3
10-2
10-1
10-6
10-5
10-4
10-3
10-2
10-1
4 m
d)
P(f
)
f (1/month)
r4
10-3
10-2
10-1
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100 6 m
h)
f (1/month)
r4
10-2
10-1
10-4
10-3
10-2
10-1
100
1.84+0.07
P(f
)
r1
10-2
10-1
10-5
10-4
10-3
10-2
10-1
15 m r2
10-2
10-1
10-4
10-3
10-2
10-1
9 m15 m
P(f
)
f (1/month)
r3
10-2
10-1
10-5
10-4
10-3
10-2
10-1
seismicity (1965-1970)
7 m8 m
f (1/month)
r4
4. Enguri (Georgia)
Telesca, Matcharashvili, Chelidze, Zhukova, NHESS, 12, 2479, 2012
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