Chiou and Youngs PEER-NGA Empirical Ground Motion Model for ...

Probability .
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
Data
Model
All Slip Types
0 -0.1 0.1-0.2 0.2-0.3 0.3-0.4 0.4-0.5 0.5-0.6 0.6-0.7 0.7-0.8 0.8-0.9 0.9-1.0
Hypocentral X Ratio
Figure B-4: Distributions for horizontal location of hypocenter in rupture plane derived
from data for M ≤ 6.5 earthquakes presented in Mai et al. (2005) (“Data”) and smoothed
for use in simulations (“Model”).
For each simulated rupture plane, the distance to all sites was computed in terms of RJB,
RSEIS (assuming a minimum seismogenic depth of 3 km), RRMS distance, and closest
distance to rupture, RRUP. The depth to top of rupture, ZTOR and the source-site angle
were also computed.
The values selected for use were the median values for each site from the 101
simulations. The median was chosen because most of the values enter regressions as
logs.
Figure 3 in the main text shows the ratio of the estimated values of Joyner-Boore distance
to the epicentral distance and the ratio of the estimated rupture distance to hypocentral
distance for the 702 sites associated with the 110 earthquakes analyzed.
Ken Campbell provided the distances he obtained for the 1992 Big Bear M 6.46
earthquake based on a rupture model he developed for that event. Figure B-5 compares
his estimates of RJB and RRUP to those obtained from this exercise. The values are close,
indicating that the process provides reasonable estimates of rupture distance measures
C&Y2006, Appendix B B-5