- Ground-motion model is:
- Use 3 site classes:
- Rock. V s,30 ≥ 750m∕s. About 300 records. SS = SA = 0.
- Stiff soil. 375 ≤ V s,30 < 750m∕s. About 350 records. SA = 1, SS = 0.
- Soft soil. V s,30 < 375m∕s. About 150 records. SS = 1, SA = 0
- Response parameter is displacement for 5% damping.
- Data from analogue (SMA-1, about 150 records) and digital (SSA-2, about 650 records) instruments.
Exclude some analogue records from before 1994 because of their low quality.
- Use repi because of lack of information on causative faults from which to compute rjb and because using
rhypo may introduce error due to errors in depths. Earthquakes mainly from Mw ≤ 6 so repi and rjb similar.
- Most data from 10 ≤ repi ≤ 200km. Few records from repi < 30km for Mw ≥ 6.5 hence advise model used
with caution there.
- Do not consider effect of faulting mechanism as lack of data for most earthquakes.
- Data from two regions: Zagros (about 375 records) and Alborz-central Iran (about 425 records).
- Individually baseline correct and bandpass filter all records according to the instrument type.
- Examine (not shown) residuals w.r.t. repi and Mw and as a histogram and find no trends by fitting best-fit