comparisons of darfieldand christchurch ground...
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Comparisons of Darfield and pChristchurch Ground Motions with
NGA W1 GMPEsNGA‐W1 GMPEs
David M BooreDavid M. BooreWorkshop on Update of Pacific Northwest
Portion of the U.S. National Seismic Hazard MapsPortion of the U.S. National Seismic Hazard Maps (NSHMs)
March 21‐22, University of Washington, Seattle
(http://www.geonet.org.nz/canterbury-quakes/)
Stations for which Rjb<= 200 km
-42o
-41o40'
ate:
2012
-03-
17
Cl C it t
43o
-42o40'
-42o20'
42
e ap_r
_le_
200.
draw
;D
a
Most class C sites to the north
Class C sites at greater distance may have smaller depth of sediments than
-43o40'
-43o20'
-43o
Latit
ude
chris
tchu
rch_
stat
ion_
ma northsediments than
those near Christchurch
-44o40'
-44o20'
-44o
Christchurch (M 6.1)NEHRP class DNEHRP class Chypocenter
orks
hop_
21-2
2mar
12\c
170o 171o 172o 173o 174o-45o
Longitude
e:C
:\pac
nw_w
o
1000 DarfieldChristchurchNEHRP B
NEHRP C 12-0
3-17
;Tim
e:16
:40
• Many sites with Vs30 = 275 and
500
m/s
)
NEHRP C
vs_r
jb.d
raw
;D
ate:
20660 m/s because values were estimated, not measured
• Distributions of Vs30 similar for both events
300
400
VS
30(m
NEHRP D
chur
ch_d
arfie
ld_v
s30_
v
• Most records with R<100 km are from class D sites
200
NEHRP E op_2
1-22
mar
12\c
hris
tc
1 10 100 1000
RJB (km)
:\pac
nw_w
orks
ho
Note: Some sites classified as “E” by Bradley & Cuprinovski (2011)
Comparison of Darfield and Christchurch Ground Motions
• Motions from both events at close distances are comparable
1 12-0
3-17
;Tim
e:16
:
• Apparently no or small site effect (but note difference in spatial locations for different class sites, so source effects could
1
(T=0
.2s)
(g)
2_ob
s.dr
aw;
Dat
e:20
1
compensate for site effects)
• Nonlinear soil response could have reduced motions for the larger event
0.1
ampe
dP
SA
urch
_dar
field
_psa
_t0.
2
Observed RotD50 reduced to
g
0.01
5%-d
NEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
p_21
-22m
ar12
\chr
istc
huGMRotI50 using factors from Boore (2010); maximum effect is 4% at T=5 s.
In this and subsequent1 2 10 20 100 200
RJB (km)
\pac
nw_w
orks
hopIn this and subsequent
comparisons, the Y-axis spans three orders of magnitude.
Concentrate on H components, as the 2008 NGA GMPEs were only for H.
1
12-0
3-17
;Tim
e:16
:
0.1
(T=1
.0s)
(g)
0_ob
s.dr
aw;
Dat
e:20
1
• Christchurch (M 6.1) class D motions comparable or even larger than Darfield (M 7.0) at close distances
0 01am
ped
PS
A
urch
_dar
field
_psa
_t1.
0• Darfield class C motions greater than Christchurch motions (R>50 km)
0.015%
-dNEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
p_21
-22m
ar12
\chr
istc
hu
1 2 10 20 100 200
RJB (km)
\pac
nw_w
orks
hop
0.1 12-0
3-17
;Tim
e:16
:
(T=5
.0s)
(g)
0_ob
s.dr
aw;
Dat
e:20
1
• Christchurch (M 6.1) class D motions now smaller than Darfield (M 7.0) at all distances
0.01
ampe
dP
SA
urch
_dar
field
_psa
_t5.
0• Apparent site effect small or not existent
0.0015%-d
NEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
p_21
-22m
ar12
\chr
istc
hu
1 2 10 20 100 200
RJB (km)
\pac
nw_w
orks
hop
Comparison of Observed Motions and Motions from NGA‐Motions and Motions from NGA
W1 GMPEs: Darfield
Darfield (M 7.0)
Dat
e:20
12-0
3-21
;
• Reddish GMPEs for class D
• Bluish GMPEs for class C
Don’t try to follow curves for individual1
(T=0
.2s)
(g)
mpe
s_bl
ue_r
ed.d
raw
;
• Overall comparison good
• Don’t try to follow curves for individual GMPEs
0.1
ampe
dPS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s _o
bs_n
ga_r
_le_
200.
gm
Overall comparison good
• Apparent lack of site effect in data is consistent with GMPEs
0.01
5%-d BA08, Vs30=275 m/s
CB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
ar12
\dar
field
_psa
_t0.
2_
1 2 10 20 100 200
RJB (km)
orks
hop_
21-2
2ma
1Darfield (M 7.0)
Dat
e:20
12-0
3-21
;
0.1(T=1
.0s)
(g)
mpe
s_bl
ue_r
ed.d
raw
;
• Note separation in observed class D values; GMPEs predictions between the two groups
0.1
ampe
dPS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s _o
bs_n
ga_r
_le_
200.
gm• Site effect in GMPEs, but not apparent in observations (but little overlap in distance range for class C and D)
0.015%
-d BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
ar12
\dar
field
_psa
_t1.
0_
1 2 10 20 100 200
RJB (km)
orks
hop_
21-2
2ma
Darfield (M 7.0)
Dat
e:20
12-0
3-21
;
0.1
(T=5
.0s)
(g)
mpe
s_bl
ue_r
ed.d
raw
;
• GMPEs underpredict observations (except class C at greater distances)
• Site effect in GMPEs, but not
0.01
ampe
dPS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s _o
bs_n
ga_r
_le_
200.
gmapparent in observations (but little overlap in distance range for class C and D)
0.001
5%-d BA08, Vs30=275 m/s
CB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
ar12
\dar
field
_psa
_t5.
0_
1 2 10 20 100 200
RJB (km)
orks
hop_
21-2
2ma
Comparison of Observed Motions and Motions from NGA‐Motions and Motions from NGA
W1 GMPEs: Christchurch
1
Christchurch (M 6.1)
;D
ate:
2012
-03-
2
1
A(T
=0.2
)(g)
gmpe
s_bl
ue_r
ed.d
raw
• Overall comparison good
• Apparent lack of site effect in data is consistent with GMPEs
0.1
dam
ped
PS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s .2
_obs
_nga
_r_l
e_20
0.
0.01
5%-d BA08, Vs30=275 m/s
CB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
12\c
hris
tchu
rch_
psa_
t0
1 2 10 20 100 200
RJB (km)
ksho
p_21
-22m
ar1
1 Christchurch (M 6.1)
;D
ate:
2012
-03-
2
0.1
A(T
=1.0
)(g)
gmpe
s_bl
ue_r
ed.d
raw
• GMPEs tend to underpredict class D motions at close distances
• Site effect in GMPEs, but not
0 01dam
ped
PS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s .0
_obs
_nga
_r_l
e_20
0.apparent in observations (but little overlap in distance range for class C and D)
0.015%
-d BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
12\c
hris
tchu
rch_
psa_
t1
1 2 10 20 100 200
RJB (km)
ksho
p_21
-22m
ar1
0.1Christchurch (M 6.1)
;D
ate:
2012
-03-
2
0.01A(T
=5.0
)(g)
gmpe
s_bl
ue_r
ed.d
raw
• GMPEs severely underpredict observations at shorter distances
• Agreement better for greater 0.01
dam
ped
PS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/sBA08 Vs30=275 m/s .0
_obs
_nga
_r_l
e_20
0.distances
• Site effect in GMPEs, but not apparent in observations (but little overlap in distance range for class C
0.0015%-d BA08, Vs30=275 m/s
CB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
12\c
hris
tchu
rch_
psa_
t5and D)
1 2 10 20 100 200
RJB (km)
ksho
p_21
-22m
ar1
Sensitivity of Predicted T=5 s PSA to sediment depth and toto sediment depth and to
magnitude
• Show AS08 and class D onlyShow AS08 and class D only
• Z1.0=1000 m from Bradley & Cuprinovski (2011)
• M 6 33 from Holden (2011) 0.1Christchurch (M 6.1)
2_6.
33.d
raw
;D
M 6.33 from Holden (2011)
• Use of these data in NGA-W2 without Z1.0 and larger M could result in biased results. T=
5.0)
(g)
ompa
re_z
sed.
add_
m6.
2
• Does Z1.0 vary spatially, with it being smaller for stations at greater distances? If so, this would help explain the
0.01
ampe
dPS
A(T
00.c
lass
_d_a
s_on
ly.c
o
p pdiscrepancy at greater distance. This could also be due to a difference in geometrical spreading due to lateral changes in crustal structure
0.0015%-d
aNEHRP Class DAS08, Vs30=275 m/s, Z1.0=480 mAS08, Vs30=275 m/s, Z1.0=1000 mAS08, as above, M 6.2AS08, as above, M 6.33
_t5.
0_ob
s_ng
a_r_
le_2
in crustal structure.
1 2 10 20 100 200
RJB (km)
r12\
chris
tchu
rch_
psa_
Vertical MotionVertical Motion
(Fry et al., 2011)
(Bradley & Cuprinovski, 2011)
Effects Producing Spatial Variability inEffects Producing Spatial Variability in Ground Motions
•Source: Radiation Pattern & Directivity•Path: volcanic vs sedimentsPath: volcanic vs sediments•Basin Waves•Sediment Depth•Shallow Site Response
•LinearN li•Nonlinear
Fault Normal and Fault Parallel Velocity Time Seri
00
HVSC,Fault Normal,158
00
CMHS,Fault Normal,158
00
PRPC,Fault Normal,158SHLC,Fault Normal,158
0 20 40 60 80
-100
050
10
Time (Sec)
Vel
ocity
(cm
/s)
HVSC F lt P ll l 68
0 20 40 60 80
-100
050
10
Time (Sec)
Vel
ocity
(cm
/s)
CMHS F lt P ll l 68
0 10 20 30 40 50
-100
050
10Time (Sec)
Vel
ocity
(cm
/s)
PRPC F lt P ll l 68
10 20 30 40
Time (Sec)
SHLC F lt P ll l 68 CMHSCMHSPRPCPRPCSHLCSHLC
HVSCHVSCSHLC, PRPC,CMHSSHLC, PRPC,CMHS0 20 40 60 80
-100
050
100
Time (Sec)
Velo
city
(cm
/s)
HVSC,Fault Parallel,68
0 20 40 60 80
-100
050
100
Time (Sec)
Velo
city
(cm
/s)
CMHS,Fault Parallel,68
0 10 20 30 40 50
-100
050
100
Time (Sec)
Velo
city
(cm
/s)
PRPC,Fault Parallel,68
10 20 30 40
Time (Sec)
SHLC,Fault Parallel,68 CMHSCMHS
LPCCLPCC
S C, C,C SS C, C,C S
5010
0
cm/s
)
LPCC,Fault Normal,158
65° Dip0 20 40 60 80
-100
0
Time (Sec)
Vel
ocity
(c
100
LPCC,Fault Parallel,68
0 20 40 60 80
-100
050
1
Time (Sec)
Velo
city
(cm
/s)• Drastic change in frequency
content going from sites on rock (HVSC & LPCC) to sites oc ( SC & CC) to s teson Quaternary sediments.
(from B. Chiou)
Evidence for Nonlinear Soil Response
0.5
1
g
NNBS
Tim
e:21
:09:
00
-0.5
0
as7
7wg
w;
Dat
e:20
12-0
3-17
;T
10 15 20 25-1
0
0.5g 2_
NN
BS
_V2A
.xls
.dra
w
-0.5
0
as1
3eg
011\
2011
0221
_235
142
10 15 20 25-1
0.5
1
g eala
nd_c
hris
tchu
rch_
2
-0.5
0
aup
g
File
:C:\n
ew_z
e
10 15 20 25-1
Time (s)
200
400
/s)
2001 M 6.8 Nisqually (SDS)
NS
-200
0
200
Acc
el(c
m/s
/
me:
08:0
9:29
20 30 40 50-400
200
400/s
) EW
Dat
e:20
12-0
3-18
;Tim
-200
0
Acc
el(c
m/s
/
_200
1\sd
s_un
filt.d
raw
;
(see Frankel et al., 2002, for details)
20 30 40 50-400
100
200
s/s)
UD File
:C:\n
isqu
ally
_
-100
0
Acc
el(c
m/s
20 30 40 50-200
Time (s)
Negative vertical accelerations are “clipped”. This may be due to a different nonlinear process than that producing the cusps shown in the previous figures.
(Fry et al., 2011)
p g
Conclusions• M 7.0 Darfield and M 6.1 Christchurch motions similar
for close distances, short periods• M 7.0 Darfield motions higher than M 6.1 Christchurch
motions for longer periods (as expected from the difference in magnitudes)
• Site response not too obvious, but this may be because of the different spatial distributions of the site classes (most close sites are class D)
• Observed motions influenced by many effects, including• Lateral changes in geology• Local linear and nonlinear site response
B i (?)• Basin waves (?)
• GMPEs are in reasonable agreement with observations for close distances, short periods
d di l i d i i• GMPEs underpredict longer period motions, using metadata in current NGA‐W2 flatfile
ENDEND
From B. Chiou, Source: GNS Science
(Bradley & Cuprinovski, 2011)
(Bradley & Cuprinovski, 2011)
Directivity Effect and Velocity Pulse
HVSCHVSC
SHLC, PRPC,CMHSSHLC, PRPC,CMHSLPCCLPCC
S C, C,C SS C, C,C S
65° Dip
Source: George Walker
(from B. Chiou)
(Bradley & Cuprinovski, 2011)
(Bradley & Cuprinovski, 2011)
0282 Christchurch, New Zealand
3.4
-43
)SHLC
PRPC
CMSH
-43.
6La
titud
e (° CMSH
HVSC
LPCC
-43.
8
172 4 172 6 172 8 173172.4 172.6 172.8 173Longitude (°)
(from B. Chiou)
Fault RuptureFault Rupture
• Reverse faulting on a buried faultReverse faulting on a buried fault• Assumed fault plane
St ik 68° (f USGS CMT)– Strike = 68° (from USGS CMT)– 65 ° dip, to the south
( )– Top of rupture is at 2 km depth (assumed)– Bottom of rupture is at 12 km (assumed)– Rupture length ~ 15 km (length of the aftershock zone).
(from B. Chiou)
300
2001 Nisqually, Washington, earthquake (M 6.8)
SDS (NS) filt d SDS filt d f 10 20 H
0
100
200
on(c
m/s
ec2 )
0
50
11:0
4:41
SDS (NS): unfiltered SDS: filtered from 10--20 Hz
• SDS within 200 m of SDN
-300
-200
-100
Acc
eler
ati
-50
filt_
filt.d
raw
;D
ate:
2003
-09-
17;
Tim
e:• liquefaction at SDS, not at SDN• Note cusps at SDS and increased
20 30 40 50 20 30 40 50
100
200
300
m/s
ec2 )
50
\rec_
proc
_stro
ng_m
otio
n\sd
s_sd
n_un
f
SDN: filtered from 10--20 HzSDN (NS): unfiltered
amplitude at high frequencies
200
-100
0
100
ccel
erat
ion
(cm
50
0
File
:C:\m
etu_
03\
20 30 40 50-300
-200
Time (sec)
Ac
20 30 40 50
-50
Time (sec)
(after Frankel et al., 2002)
0.1Christchurch (M 6.1)
d.dr
aw;
Dat
e:20
0 01(T=5
.0)(
g)
blue
_red
.com
pare
_zse
d
0.01
dam
ped
PS
A
NEHRP Class DNEHRP Class C ga
_r_l
e_20
0.gm
pes_
b
0.0015%-d
NEHRP Class CAS08, Vs30=275 m/s, Z1.0=480 mAS08, Vs30=275 m/s, Z1.0=1000 mCB08, Vs30=275 m/s, Z1.0=326 mCB08, Vs30=275 m/s, Z1.0=1000 mCY08, Vs30=275 m/s, Z2.5=2.5 kmCY08, Vs30=275 m/s, Z2.5=4.1 km hu
rch_
psa_
t5.0
_obs
_n
1 2 10 20 100 200
RJB (km)
2.5
1-22
mar
12\c
hris
tch
0.1Christchurch (M 6.1)
_m6.
2.dr
aw;
Dat
0 01(T=5
.0)(
g)
ed.c
ompa
re_z
sed.
add_
0.01
dam
ped
PS
A
NEHRP Class DNEHRP Class C _l
e_20
0.gm
pes_
blue
_re
0.0015%-d
NEHRP Class CAS08, Vs30=275 m/s, Z1.0=480 mAS08, Vs30=275 m/s, Z1.0=1000 mAS08, as above, M 6.2CB08, Vs30=275 m/s, Z1.0=326 mCB08, Vs30=275 m/s, Z1.0=1000 mCY08, Vs30=275 m/s, Z2.5=2.5 km _p
sa_t
5.0_
obs_
nga_
r_
1 2 10 20 100 200
RJB (km)
CY08, Vs30=275 m/s, Z2.5=4.1 km
mar
12\c
hris
tchu
rch_
(Bradley & Cuprinovski, 2011)
-41o40'Darfield (M 7.0)
NEHRP class DNEHRP l C
2012
-03-
17;T
-42o40'
-42o20'
-42o NEHRP class Chypocenter
_r_l
e_20
0.dr
aw;
Dat
e:
Stations for which Rjb<= 200 km
-43o40'
-43o20'
-43o
Latit
ude
\dar
field
_sta
tion_
map
_
-44o40'
-44o20'
-44o
wor
ksho
p_21
-22m
ar12
\
169o 170o 171o 172o 173o 174o-45o
Longitude
le:C
:\pac
nw_w
1
03-1
7;Ti
me:
16:1
5
0.1) bs.d
raw
;D
ate:
2012
-0
PG
A(g
hurc
h_da
rfiel
d_pg
a_ob
0.01
NEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
op_2
1-22
mar
12\c
hris
tch
1 2 10 20 100 200
RJB (km)
C:\p
acnw
_wor
ksho
1
2-03
-17;
Tim
e:16
:
0.1(T
=2.0
s)(g
)
_obs
.dra
w;
Dat
e:20
12
0.01ampe
dP
SA
(
rch_
darfi
eld_
psa_
t2.0
_
5%-d
a
NEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
_21-
22m
ar12
\chr
istc
hur
1 2 10 20 100 2000.001
RJB (km)
\pac
nw_w
orks
hop_
100
03-1
7;Ti
me:
16:1
5
10
/s)
bs.d
raw
;D
ate:
2012
-0
PG
V(c
m/
hurc
h_da
rfiel
d_pg
v_ob
1
NEHRP Class D (Darfield, M 7.0)NEHRP Class D (Christchurch, M 6.1)NEHRP Class C (Darfield, M 7.0)NEHRP Class C (Christchurch, M 6.1)
op_2
1-22
mar
12\c
hris
tch
1 2 10 20 100 200
RJB (km)
C:\p
acnw
_wor
ksho
Observed RotD50
1 Darfield (M 7.0)
te:2
012-
03-2
0;Ti
m
Observed RotD50 reduced to GMRotI50 using factors from Boore (2010); maximum effect is 4% at T=5 s. 0.1) s_
blue
_red
.dra
w;
Dat
at 5 s
In this and subsequent comparisons, the Y-axis spans three orders of magnitude.
PG
A(g
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s s_
nga_
r_le
_200
.gm
pes
Concentrate oh H components, as the 2008 NGA GMPEs were only for H.
0.01 BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s
mar
12\d
arfie
ld_p
ga_o
bs
1 2 10 20 100 200
RJB (km)
,
_wor
ksho
p_21
-22m
1Darfield (M 7.0)
Dat
e:20
12-0
3-20
;
0 1(T=2
.0s)
(g)
pes_
blue
_red
.dra
w;
D
0.1
ampe
dP
SA
(
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s ob
s_ng
a_r_
le_2
00.g
mp
0.01
5%-d
a BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s r1
2\da
rfiel
d_ps
a_t2
.0_o
1 2 10 20 100 200
RJB (km)
,
orks
hop_
21-2
2mar
100
Darfield (M 7.0)
te:2
012-
03-2
0;Ti
m
100
/s)
s_bl
ue_r
ed.d
raw
;D
at
10
PG
V(c
m/
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s s_
nga_
r_le
_200
.gm
pes
1
BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s m
ar12
\dar
field
_pgv
_obs
1 2 10 20 100 200
RJB (km)
,
_wor
ksho
p_21
-22m
1 Christchurch (M 6.1)
Dat
e:20
12-0
3-21
;
0.1) pes_
blue
_red
.dra
w;
D
PG
A(g
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s ob
s_ng
a_r_
le_2
00.g
mp
0.01 BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s r1
2\ch
ristc
hurc
h_pg
a_o
1 2 10 20 100 200
RJB (km)
,
orks
hop_
21-2
2mar
1Christchurch (M 6.1)
Dat
e:20
12-0
3-2
0.1(T
=2.0
)(g)
mpe
s_bl
ue_r
ed.d
raw
;
0.01
dam
ped
PS
A
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s 0_
obs_
nga_
r_le
_200
.g
5%-d BA08, Vs30=275 m/s
CB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s 2\
chris
tchu
rch_
psa_
t2.0
1 2 10 20 100 2000.001
RJB (km)
,
ksho
p_21
-22m
ar12
100 Christchurch (M 6.1)
Dat
e:20
12-0
3-21
;
10
/s)
pes_
blue
_red
.dra
w;
D
1
PG
V(c
m/
NEHRP Class DNEHRP Class CAS08, Vs30=275 m/s ob
s_ng
a_r_
le_2
00.g
mp
1 BA08, Vs30=275 m/sCB08, Vs30=275 m/sCY08, Vs30=275 m/sAS08, Vs30=660 m/sBA08, Vs30=660 m/sCB08, Vs30=660 m/sCY08, Vs30=660 m/s r1
2\ch
ristc
hurc
h_pg
v_o
1 2 10 20 100 200
RJB (km)
,
orks
hop_
21-2
2mar
(Fry et al., 2011)
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