- Ground-motion model is:
where A is in g, C1 = -2.7809, C2 = 0.5344, C3 = -0.0015 and σ = 0.392 (stated to be in terms of
natural logarithms although GMPE presented in terms of log).
- Purpose of develop GMPE is for rapid assessment of PGA following earthquake and, therefore, no
distinction made between rock and soil sites.
- Focal depths between 2 and 22km.
- All records from 1999 Kocaeli (Izmit) and Düzce earthquakes and their aftershocks from 132 permanent
and temporary stations.
- Earthquakes are mainly strike-slip but some have normal mechanisms. Believe that model should only be
used for these types of mechanisms.
- Baseline and instrument correct records. Examine Fourier amplitude spectra to select the high- and
low-pass filters. Use the Basic strong-motion Accelerogram Processing (BAP) software: high-cut filtering
with a cosine shape and then low-cut bi-directional second-order Butterworth filtering (after padding with
- Select data with Mw ≥ 4.
- Distance saturation term (0.0183 × 100.4537Mw) within the log 10 given by square root of rupture area
estimated by regression analysis on areas for the two mainshocks and the equations of Wells and
Coppersmith (1994) for other earthquakes.
- Compare observed and predicted PGAs for different Mw.
- State that GMPE can be used for 4 ≤ Mw ≤ 7.5 and distances ≤ 200km.
- Note that site effects should be included within the model but currently lack of information.