UC Berkeley Seismological Laborarory Moment Tensor Homepage

Moment Tensor Homepage

The Berkeley Seismological Laboratory (BSL) routinely determines moment tensors for events occurring in Central and Northern California, and notable earthquakes in the western US. The BSL is operating two automated moment tensor methodologies under the Rapid Earthquake Data Integration (REDI) project. With these two methods, namely a surface wave spectral inversion and a three-component complete waveform inversion we determine preliminary (automatic) moment tensor solutions 6-9 minutes after the occurrence of an earthquake. Analyst reviewed solutions are disseminated via email and are posted to an online catalog (link below).

Example of the automatic solution obtained within minutes after the occurrence of the September 28, 2004 Mw6.0 Parkfield earthquake. After review the moment tensor is disseminated via the internet and by email. Compare the reviewed solution.

Moment tensor catalog and format description.

This catalog is revised as more information becomes available.

NCEDC Moment Tensor Archive

BSL Moment Tensor References

Earthquakes of Special Interest

Annual Moment Tensor Maps (last updated January 19, 2011)

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