- Ground-motion model is:
where a is in cm∕s2, for N.E. China A = -0.474, B = 0.613, C = -0.873 and D = -0.00206 (σ not given)
and for S.W. China A = 0.437, B = 0.454, C = -0.739 and D = -0.00279 (σ not given).
- Consider two site conditions for NE records but do not model:
- Rock: 28 records.
- Soil: 45 records.
- Consider all records to be free-field.
- Note that Chinese surface-wave magnitude, M, is different than Ms and may differ by 0.5 or more. Use
mb or Ms and find larger residuals.
- Most records from M ≤ 5.8.
- Note isoseismals are not elongated for these earthquakes so use of another distance measure will not change
results by much.
- Also derives equation for SW China (3.7 ≤ M ≤ 7.2, 6.0 ≤ R ≤ 428.0km all but one record ≤ 106.0km
, 36 records from 23 earthquakes) and note difference between results from NE China although use less
- Note that some scatter may be due to radiation pattern.
- Note that data is from limited distance range so need more data to confirm results.