Introduction

This is a project designed to provide a number of functions related to parsing and processing earthquake ground motion data, building on top of the ObsPy library. Most of the extensions that we provide are to handle strong motion data and related issues.

Documentation

• Please note, we are in the process of improving the documentation and that there are some incomplete sections.
• The full documentation can be viewed locally by running the docs/makedocs.sh script.
• The documentation is also available here.
• The MATLAB functions included in the tools/matlab directory include a short tutorial

Getting Help

The developers can be reached at gmprocess@usgs.gov.

If you would like to post an issue, ask a question, request a new feature, or report a bug, you can do so at here in Work Items. This GitLab instance, however, is restricted to registered users, and registering a user is not immediate or automatic, requiring an internal approval process. Posting issues is easier on GitHub, and the developers of this repository monitor the groundmotion-processing-github repository's issues to alleviate need to deal with the code.usgs.gov restrictions.

If you would like to contribute merge requests to this repository, please let us know and we can assist you in registering an account at code.usgs.gov.

Suggested Citation

If you wish to cite this software please cite:

• Thompson, E.M., M. Hearne, B.T. Aagaard, J.M. Rekoske, C.B. Worden, M.P. Moschetti, H.E. Hunsinger, G.C. Ferragut, G.A. Parker, J.A. Smith, K.K. Smith, and A.R. Kottke (2024). USGS Automated Ground Motion Processing Software Version 2, U.S. Geological Survey software release, doi: 10.5066/P13HMKFJ.

• Thompson, E.M., M. Hearne, B.T. Aagaard, J.M. Rekoske, C.B. Worden, M.P. Moschetti, H.E. Hunsinger, G.C. Ferragut, G.A. Parker, J.A. Smith, Smith, K.K., and A.R. Kottke (2025). Automated, Near Real‐Time Ground‐Motion Processing at the US Geological Survey. Seismological Research Letters, 96(1), pp.538-553, doi: 10.1785/0220240021.

Journal Articles

The list below is a subset of articles that made use of this software in their study. If you would like to have an article added to this list, please open an issue or email the developers.

• Ahdi, S.K., B.T. Aagaard, M.P. Moschetti, G.A. Parker, O.S. Boyd, and W.J. Stephenson (2024). Empirical ground-motion basin response in the California Great Valley, Reno, Nevada, and Portland, Oregon. Earthquake Spectra, 40(2): 1099-1131, doi: 10.1177/87552930241237250.

• Boyd OS, D. Churchwell, M.P. Moschetti, et al. (2024). Sediment thickness map of United States Atlantic and Gulf Coastal Plain Strata, and their influence on earthquake ground motions. Earthquake Spectra, 40(1): 89-112, doi: 10.1177/87552930231204880.

• Chatterjee, A., D.T. Trugman, G. Hirth, J. Lee, and V.C. Tsai (2024). High‐frequency ground motions of earthquakes correlate with fault network complexity. Geophysical Research Letters, 51(12), doi: 10.1029/2024GL109418.

• Hirakawa, E., G.A. Parker, A. Baltay, and T. Hanks (2023). Rupture directivity of the 25 October 2022 Mw 5.1 Alum Rock earthquake. The Seismic Record, 3(2): 144-155, doi: 10.1785/0320230013.

• Ji, C., A. Cabas, A. Kottke, M. Pilz, J. Macedo, and C. Liu (2023). A DesignSafe earthquake ground motion database for California and surrounding regions. Earthquake Spectra, 39(1): 702–721, doi: 10.1177/87552930221141108.

• Li, M., E.M. Rathje, J.P. Stewart, M.E. Ramos-Sepulveda, and Y.M. Hashash (2025). Regional adjustment to the NGA-East GMM for Texas, Oklahoma, and Kansas. Earthquake Spectra, doi: 10.1177/87552930251313817.

• Mohammed, S., R. Shams, C.C. Nweke, T.E. Buckreis, M.D. Kohler, Y. Bozorgnia, and J.P. Stewart (2024). Usability of Community Seismic Network recordings for ground-motion modeling. Earthquake Spectra, 40(4): 2598-2622, doi: 10.1177/87552930241267749.

• Moschetti M.P., E.M. Thompson, J.M. Rekoske, M. Hearne, P. Powers, D. McNamara, and C. Tape (2019). Ground‐Motion Amplification in Cook Inlet Region, Alaska, from Intermediate‐Depth Earthquakes, Including the 2018 7.1 Anchorage Earthquake. Seismological Research Letters, 91(1): 142–152, doi: 10.1785/0220190179.

• Moschetti, M.P., B.T. Aagaard, S.K. Ahdi, J. Altekruse, O.S. Boyd, A.D. Frankel, J. Herrick, M.D. Petersen, P.M. Powers, S. Rezaeian, and A.M. Shumway (2024). The 2023 US national seismic hazard model: Ground-motion characterization for the conterminous United States. Earthquake Spectra, 40(2): 1158-1190, doi: 10.1177/87552930231223995.

• Parker, G.A., and A.S. Baltay (2022). Empirical Map‐Based Nonergodic Models of Site Response in the Greater Los Angeles Area. Bulletin of the Seismological Society of America, 112(3): 1607–1629, doi: 10.1785/0120210175

• Rekoske J.M., E.M. Thompson, M.P. Moschetti, M. Hearne, B.T. Aagaard, and G.A. Parker (2020). The 2019 Ridgecrest, California, Earthquake Sequence Ground Motions: Processed Records and Derived Intensity Metrics. Seismological Research Letters, 91(4): 2010–2023, doi: 10.1785/0220190292

Disclaimer

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.