Verification & Validation
A simulated seismogram is only worth something if it resembles what a seismometer actually recorded. For each earthquake below we ran the SCEC Broadband Platform, fetched the real recordings from the same stations, and compared them. Every report is published in full — the bias, the per-period breakdown, the spectra and the caveats.
A single pass mark is not the whole answer. The verdict below is the mean bias across spectral periods. On every run to date the mean sits inside the declared band while individual periods — 1 second in particular — sit outside it. Open a report to see the per-period breakdown before drawing an engineering conclusion.
What the metric is. Mean |bias| is ln(observed / simulated) RotD50 spectral acceleration, averaged over stations. A bias of 0.69 is a factor of two. The pass band is declared before each run, not chosen after seeing the result.
| Earthquake | Simulation | Verdict | Mean bias | Stations | Periods | |
|---|---|---|---|---|---|---|
|
11 km N of Redwood Valley, CA
M5.6 2026-06-24 |
BBP simulated |
Mean within band
1 period out of band |
1.45×
band 1.99× |
40 | 63 | Report → |
|
15km WSW of Ferndale, CA
M6.4 2022-12-20 |
BBP simulated | Mean within band |
1.18×
band 1.99× |
31 | 63 | Report → |
|
Ridgecrest Earthquake Sequence
M7.1 2019-07-06 |
BBP simulated |
Mean within band
1 period out of band |
1.27×
band 1.99× |
30 | 63 | Report → |
|
Ridgecrest Earthquake Sequence
M6.4 2019-07-04 |
BBP simulated |
Mean within band
1 period out of band |
1.4×
band 1.99× |
36 | 63 | Report → |
|
The 2014 South Napa, California Earthquake
M6.0 2014-08-24 |
BBP simulated |
Mean within band
3 periods out of band |
1.72×
band 1.99× |
40 | 63 | Report → |
5 reports published. Reports are generated automatically after a simulation completes for an event with enough nearby recordings.