- Ground-motion model is: where Y is in g, c1 = 0.14, c2 = -6.25, c3 = 0.37, c4 = 2.237, c5 = -7.542, c6 = -0.125, c7 = 1.19, c8 =
-6.15, c9 = 0.6, c10 = 0.345, bv = -0.24, V A = 484.5; τ = 0.435 (inter-event), ϕ = 0.508 (intra-event) and
σ = 0.669 (total) for homoscedastic variability; and τ(M) = s1 for M ≤ 7.1, τ(M) = s1+(s2-s1)(Mw-7.1)
for 7.1 < Mw < 7.5 and τ(M) = s2 for Mw ≥ 7.5 where s1 = 0.28 and s2 = 0.04, τ(M,R) = τ(M) + r1
for R ≤ 100km, τ(M,R) = τ(M) + (r1 - r2)(R - 100) for 100 < R < 130km and τ(M,R) = τ(M) + r2
for R ≥ 130km where r1 = 0.30 and r2 = 0.52 for heteroscastic inter-event variability.
- Characterise sites using V s,30. State that valid between 200 and 1300m∕s.
- Use Bdepth (depth to 1.5km∕s shear-wave velocity isosurface), which ranges from about 100m to about
2400m. Only 353 records have estimates of Bdepth. Believe model applicable for Bdepth between 0 and
- Use 3 styles of faulting:
- Strike-slip (1120 records) and normal (13 records). F = 1.0.
- Reverse (1450 records). F = 1.28.
- Reverse/strike-slip oblique. F = 1.14.
- Update of model of Graizer and Kalkan (2007, 2008) (see Section 2.279) to include anelastic attenuation
term based on Q0, the regional quality factor, and a frequency-dependent sedimentary-basin scaling term
based on Bdepth. Use same database as Graizer and Kalkan (2007, 2008).
- Choose c10 = 0.345 based on average Q0 = 150 for California. Recommend using model with Q0 determined
from Lg or coda waves for region of interest. Believe model applicable for Q0 ≤ 250.
- Constrain coefficients of basin-effect terms using data from 1999 Mw7.1 Hector Mine, 1992 Mw7.3 Landers
and 1989 Mw6.9 Loma Prieta earthquakes.
- Analyse inter- and intra-event residuals using best-fit lines against various independent parameters and
find no trends or large offsets.
- Provide model for pseudo-spectral accelerations. This is not summarised hear because it is not in the style
of coefficients for many periods but as a closed-form function.
- Define heteroscastic variability models by dividing standard deviations into 8 magnitude and 10 distance
- Compare observations and predictions for 13 Californian earthquakes and find a good match.