Max Est. MMI
Ridgecrest Earthquake Sequence
Shaking Animations
Simulated bowling pin shaking at each city’s intensity level. Videos appear as they finish rendering.
BBP Simulation Comparison
How closely a physics-based simulation of this earthquake reproduces what the seismic network actually recorded. The simulation is run on the SCEC Broadband Platform and compared against real seismograms station by station.
Show ▼
BBP Simulation Comparison
How closely a physics-based simulation of this earthquake reproduces what the seismic network actually recorded. The simulation is run on the SCEC Broadband Platform and compared against real seismograms station by station.
Emulated hardware. The simulation ran on arm64 under emulation. Amplitudes are not SCEC-reference-accurate, and this measurement cannot separate the platform from the model.
One realization. A single stochastic rupture, not an ensemble. The bias below is one draw; a second run with a different seed would give a different number.
What a pass means. Consistency with recordings at these 36 stations, for this event, under this velocity model, on this hardware, within a factor of 1.99. It is not a general statement about BBP and not a prediction of accuracy at an unrecorded site.
- mean |bias|
- 0.336
- a factor of 1.4×
- pass band
- 0.69
- a factor of 1.99×, declared before the run
- sigma
- 0.444
- station-to-station scatter
- cross-check
- 0.428
- recomputed here from the waveforms
The metric is ln(observed / simulated) RotD50 spectral acceleration, averaged over stations. Positive means the simulation under-predicts — real shaking was larger. Basis: BBP RotD50 residuals (authoritative).
Residual by period
Mean ln(obs/sim) at each spectral period. A structure responds at its own period, so agreement at one period says nothing about another.
| Period | Bias | Simulation | vs. band |
|---|---|---|---|
| 0.1s | -0.367 | over-predicts by 44% | within |
| 0.3s | -0.514 | over-predicts by 67% | within |
| 1s | -0.822 | over-predicts by 127% | outside band |
| 3s | -0.216 | over-predicts by 24% | within |
Goodness of fit across the spectrum
Mean residual with its ±1σ band, against the pass band. Diamonds are the Broadband Platform’s own RotD50 residuals.
Engineering Ground Motion Parameters
GMPE predictions provide an independent check on the ShakeMap interpolated intensities above.
ShakeMap relies on seismic station recordings; in areas with sparse station coverage — or
for large teleseismic events and earthquakes outside dense West Coast networks — ShakeMap
MMI can be inaccurate. A significant difference between ShakeMap and GMPE estimates is a signal
that the ShakeMap result should be treated as preliminary.
Also includes site Vs30 values and raw ground motion parameters (PGA/PGV).
Show ▼
Engineering Ground Motion Parameters
GMPE predictions provide an independent check on the ShakeMap interpolated intensities above. ShakeMap relies on seismic station recordings; in areas with sparse station coverage — or for large teleseismic events and earthquakes outside dense West Coast networks — ShakeMap MMI can be inaccurate. A significant difference between ShakeMap and GMPE estimates is a signal that the ShakeMap result should be treated as preliminary. Also includes site Vs30 values and raw ground motion parameters (PGA/PGV).
Est. Vs30 Values
Estimated shear-wave velocity in the upper 30 m used in GMPE calculations. Ref. column shows the 760 m/s rock-site reference for comparison.
| Location | Ref. (760 m/s) | Est. Vs30 (m/s) |
|---|---|---|
|
Ridgecrest
CA |
760 | 294 |
|
China Lake Acres
CA |
760 | 294 |
|
Inyokern
CA |
760 | 294 |
|
Searles Valley
CA |
760 | 352 |
|
California City
CA |
760 | 294 |
|
Fort Irwin
CA |
760 | 352 |
|
Edwards Air Force Base
CA |
760 | 709 |
|
Bodfish
CA |
760 | 710 |
|
Lake Isabella
CA |
760 | 357 |
|
Weldon
CA |
760 | 294 |
|
Lone Pine
CA |
760 | 294 |
|
Kernville
CA |
760 | 352 |
|
Lenwood
CA |
760 | 363 |
|
Wofford Heights
CA |
760 | 667 |
MMI vs Distance — Default Vs30 (760 m/s)
All methods using the 760 m/s rock-site reference. ShakeMap values are independent of Vs30.
MMI vs Distance — Est. Vs30
GMPEs use the Est. Vs30 values shown in the table above. ShakeMap values are independent of Vs30.
GMPE Residual — Observed − Predicted MMI
Signed residual at each seismic station. Positive values mean the GMPE underestimated shaking; negative values mean it overestimated. The dashed line at zero indicates perfect agreement.
GMPE Predicted vs. Observed MMI at Seismic Stations
Each point is one seismic station. Points on the dashed 1:1 line indicate perfect agreement; above the line = GMPE underestimated shaking; below = overestimated.
GMPE Performance — Station Observations
Statistics computed by comparing each GMPE's predicted MMI against ShakeMap observed MMI at seismic stations. Bias = mean(observed − predicted). Lower RMSE indicates better overall agreement with instrumental measurements.
| GMPE | Bias | Sigma | RMSE |
|---|---|---|---|
| ASK14 | +1.75 | 0.78 | 1.92 |
| BSSA14 | +1.73 | 0.78 | 1.90 |
| CY14 | +1.70 | 0.73 | 1.85 |
| CB14 | +1.83 | 0.79 | 2.00 |
Peak Ground Motion — Seismic Station Observations
Recorded PGA and PGV at seismic stations, sorted by highest PGA. Top 25 stations shown. MMI (PGA) and MMI (PGV) are independent conversions via Worden et al. (2012) GMICE.
| Station | PGA (g) | MMI (PGA) | PGV (cm/s) | MMI (PGV) |
|---|---|---|---|---|
| Christmas Canyon China Lake (CI.CCC) | 0.3817 | Strong(VI) | 26.583 | Severe(VIII) |
| Lakeland Street, Ridgecrest CA (CI.Q0072) | 0.2112 | Moderate(V) | 31.192 | Violent(IX) |
| Laurel Mtn (CI.LRL) | 0.1971 | Moderate(V) | 14.036 | Severe(VIII) |
| Tower 2 (CI.TOW2) | 0.1786 | Moderate(V) | 15.626 | Severe(VIII) |
| Snort (CI.SRT) | 0.1577 | Moderate(V) | 17.745 | Severe(VIII) |
| Volcano Peak 2 (CI.WVP2) | 0.0983 | Moderate(V) | 4.742 | Strong(VI) |
| Nine Mile Canyon (CI.WNM) | 0.0931 | Moderate(V) | 2.214 | Moderate(V) |
| Bird Spring (CI.WBS) | 0.0912 | Moderate(V) | 3.986 | Strong(VI) |
| Lake Isabella - Kern River Valley (CE.34349) | 0.0646 | Light(IV) | 4.189 | Strong(VI) |
| Death Valley - Shoshone (CE.32076) | 0.0641 | Light(IV) | 4.599 | Strong(VI) |
| Lancaster - 15th & W Avenue J (CE.24661) | 0.0596 | Light(IV) | 5.849 | Strong(VI) |
| Onyx Ranch (CI.WOR) | 0.0563 | Light(IV) | 1.659 | Moderate(V) |
| Lucerne Valley 2 (CI.LUC2) | 0.0550 | Light(IV) | 5.471 | Strong(VI) |
| Hanning Flat (CI.WHF) | 0.0548 | Light(IV) | 2.726 | Moderate(V) |
| Palmdale - 30th St West & Ave P (CE.24967) | 0.0504 | Light(IV) | 3.884 | Strong(VI) |
| CA:Palmdale;FS 37 (NP.262) | 0.0495 | Light(IV) | 3.981 | Strong(VI) |
| Shuttle (CI.SHU) | 0.0494 | Light(IV) | 4.643 | Strong(VI) |
| Rose Valley Canyon 2 (CI.WRV2) | 0.0485 | Light(IV) | 3.934 | Strong(VI) |
| Pacoima - Kagel Canyon Fire Sta (CE.24088) | 0.0456 | Light(IV) | 3.826 | Strong(VI) |
| Apple Valley - Hwy 18 & Standing Rock Av (CE.23119) | 0.0438 | Light(IV) | 1.755 | Moderate(V) |
| Yermo - Fire Station (CE.22074) | 0.0425 | Light(IV) | 4.632 | Strong(VI) |
| Neenach (CI.NEN) | 0.0423 | Light(IV) | 6.072 | Strong(VI) |
| Shoshone (CI.SHO) | 0.0416 | Light(IV) | 3.639 | Strong(VI) |
| Barstow Service Center (CI.RRX) | 0.0413 | Light(IV) | 5.707 | Strong(VI) |
| Palmdale - 55th St East & Ave R (CE.24965) | 0.0405 | Light(IV) | 2.512 | Moderate(V) |
Ground Shaking Intensities — Interpolated ShakeMap MMI
14 sites| Location | MMI Description |
|---|---|
|
Ridgecrest
CA |
Strong(VI) |
|
China Lake Acres
CA |
Strong(VI) |
|
Inyokern
CA |
Strong(VI) |
|
Searles Valley
CA |
Moderate(V) |
|
California City
CA |
Light(IV) |
|
Fort Irwin
CA |
Light(IV) |
|
Edwards Air Force Base
CA |
Light(IV) |
|
Bodfish
CA |
Light(IV) |
|
Lake Isabella
CA |
Light(IV) |
|
Weldon
CA |
Light(IV) |
|
Lone Pine
CA |
Light(IV) |
|
Kernville
CA |
Light(IV) |
|
Lenwood
CA |
Light(IV) |
|
Wofford Heights
CA |
Light(IV) |
Seismic Station Observed MMI
MMI values are derived directly from observed ground motion measurements at seismic stations and are not spatially interpolated.