Campbell-Bozorgnia

• Two candidate models are currently being considered to capture the change in magnitude scaling of ground motion at large magnitudes

• Magnitude-scaling model– Assumes Mw alone can explain large-magnitude

scaling of ground motion

• Aspect ratio-scaling model:– Assumes Mw and aspect ratio (AR) are needed to

explain large-magnitude scaling of ground motion

5.0 5.5 6.0 6.5 7.0 7.5 8.0Moment Magnitude

10-1

100

101

102

Asp

ect

Rat

io (

L/W

)STRIKE SLIP

N. Cal. - Type ASo. Cal. - Type ANGAWC94 (W = 10)HB02 (W = 10)EL02 (W = 10)

5.0 5.5 6.0 6.5 7.0 7.5 8.0Moment Magnitude

10-1

100

101

102

Asp

ect

Rat

io (

L/W

)STRIKE SLIP

N. Cal. - Type ASo. Cal. - Type ANGAWC94 (W = 15)HB02 (W = 15)EL02 (W = 15)

5.0 5.5 6.0 6.5 7.0 7.5 8.0Moment Magnitude

10-1

100

101

102

Asp

ect

Rat

io (

L/W

)STRIKE SLIP

N. Cal. - Type ASo. Cal. - Type ANGAWC94 (W = 20)HB02 (W = 20)EL02 (W = 20)

Magnitude-Scaling Model

PGA, All Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3R

ES

IDU

AL

PGA, All Faults

0 2 4 6 8 10 12 14LW

-3

-2

-1

0

1

2

3R

ES

IDU

AL

With Surface Slip, Strike-Slip Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3R

ES

IDU

AL

PGA, W/O Surface Slip, Strike-Slip Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3R

ES

IDU

AL

Atten373 (Model 1), Resid stages 1 & 2 (combined), PGA

0 10 20 30 40 50 60RRUP

-3

-2

-1

0

1

2

3

RE

S1_

2_P

GA

Atten373 (Model 1), Resid stages 1 & 2 (combined), PGA

4 5 6 7 8M

-3

-2

-1

0

1

2

3

RE

S1_

2_P

GA

1 10 100Horizontal Distance to Fault (km)

10-2

10-1

100A

ccel

erat

ion

(g

)PGA

Campbell & Bozorgnia (2003)Campbell & Bozorgnia (Prelim NGA)

PARAMETERS:

M = 6.5, 7.0, 7.5, 8.0

Fault = Strike Slip

Dip = 90

Vs30 = 600 (C)

5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0

Moment Magnitude

10-2

10-1

100A

ccel

erat

ion

(g

)PGA

Campbell & Bozorgnia (2003)Campbell & Bozorgnia (Prelim NGA)

PARAMETERS:

Rjb = 0, 5, 10, 25

Fault = Strike Slip

Dip = 90

Vs30 = 270 (D)

0 10 20 30 40 50 60 70 80 90

Dip (degrees)

0.0

0.4

0.8

1.2

1.6

2.0

Fau

ltin

g F

acto

rSTYLE OF FAULTING

PGA - ReversePSA (1s) - ReversePGA - NormalPSA (1s) - Normal

Aspect Ratio-Scaling Model

PGA, All Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3

RE

SID

UA

L

PGA, All Faults

0 2 4 6 8 10 12 14LW

-3

-2

-1

0

1

2

3R

ES

IDU

AL

PGA, With Surface Slip, Strike-Slip Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3

RE

SID

UA

L

PGA, W/O Surface Slip, Strike-Slip Faults

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0M

-3

-2

-1

0

1

2

3

RE

SID

UA

L

5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0

Moment Magnitude

10-2

10-1

100

Acc

eler

atio

n (

g)

PGA

Campbell & Bozorgnia (NGA AR-Scaling)Campbell & Bozorgnia (NGA M-Scaling)

PARAMETERS:

Rjb = 0, 5, 10, 25

Fault = Strike Slip

Dip = 90

Vs30 = 600 (C)

5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0

Moment Magnitude

10-2

10-1

100

Ac

ce

lera

tio

n (

g)

PGA

Campbell & Bozorgnia (NGA AR-Scaling)Campbell & Bozorgnia (NGA M-Scaling)

PARAMETERS:

Rjb = 0, 5, 10, 25

Fault = Strike Slip

Dip = 90, W = 20

Vs30 = 600 (C)

Basin Effects: Influence of Depth to

Vs = 1.5 km/sec

0 1000 2000 3000 4000Z1_5

-3

-2

-1

0

1

2R

ES

1_2 _

T1