1989 Loma Prieta, SF

Plots of original ground motion, extracted pulse, and residual ground motion:

Map of epicenter, rupture extent and station location:

Ground motion information:

NGA Record Sequence Number 796

Magnitude = 6.9
Closest Distance = 77.4 km
Hypocentral Distance = 99.34 km
Vs30 = 594 m/s
Mechanism = Reverse-oblique

T_p = 1.32 s
PGV = 32.9 cm/s

Orientation of strongest pulse, relative to north = 68 degrees
Orientation of strongest pulse, relative to fault parallel = 60 degrees
Pulse in fault normal direction = 0
Pulse due to directivity = 0

Comments:

Not soft soil, but still too far away.

Directivity parameters:

X = 0.5
s = 20.02 km
θ = 20.9

Y = 0.81
d = 14.53 km
φ = 43.4

IDP = 2.38
Rowshandel parameter = 0.1

Notes:

These results were computed November 1st, 2012
These results are based on the June 2012 version of the NGA West 2 database
If you have any observations, comments or requests regarding this data, please e-mail Jack Baker and Shrey Shahi