1989 Loma Prieta, Oakland

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 784

Magnitude = 6.9
Closest Distance = 72.2 km
Hypocentral Distance = 93.33 km
Vs30 = 306 m/s
Mechanism = Reverse-oblique

T_p = 1.39 s
PGV = 36.3 cm/s

Orientation of strongest pulse, relative to north = 261 degrees
Orientation of strongest pulse, relative to fault parallel = 47 degrees
Pulse in fault normal direction = 0
Pulse due to directivity = 0

Comments:

Soft soil site. Too far away to be directivity

Directivity parameters:

X = 0.5
s = 20.02 km
θ = 30.4

Y = 0.81
d = 14.53 km
φ = 49.4

IDP = 1.96
Rowshandel parameter = 0.12

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