1 / 18

Time Dependent Estimates of the Velocity Gradient Tensor Field for Transient Detection

Time Dependent Estimates of the Velocity Gradient Tensor Field for Transient Detection. William Holt , Gina Shcherbenko, Eric Caruso, Yu Chen Acknowledgements: We thank SCEC for funding support. 0.1° x 0.1° Grid. Rigid Pacific Plate.

chill
Download Presentation

Time Dependent Estimates of the Velocity Gradient Tensor Field for Transient Detection

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Time Dependent Estimates of the Velocity Gradient Tensor Field for Transient Detection William Holt, Gina Shcherbenko, Eric Caruso, Yu Chen Acknowledgements: We thank SCEC for funding support

  2. 0.1° x 0.1° Grid Rigid Pacific Plate

  3. Model magnitude of shear strain rates (pure SS style)(SCEC4.0 Velocity field)

  4. Smoothing or Damping • Maximize signal associated with GPS • Achieve Reduced Chi-Squared misfit between model displacement and observed displacement of ~1.0 for all epochs Haines, Jackson, Holt, Agnew [1998] Beavan and Haines [2001]

  5. Time Series from SCEC IVc Red = 15 day moving average filter 4th order polynomial fit with annual and semi-annual terms Annual and semi-annual removed Green = 4th order polynomial WNRA – Phase 4c

  6. Output 2 week epoch solutions of displacement Subtract out ‘master solution’ to estimate signal only from transients -For real data we used SCEC4.0 solution as a master solution -For other groups in the SCEC exercise we used time averaged solution (2007 – 2009). 5 mm 2 Week Displacements

  7. Output 2 week epoch solutions of displacement Subtract out ‘master solution’ to estimate signal only from transients -For real data we used SCEC4.0 solution as a master solution -For other groups in the SCEC exercise we used time averaged solution (2007 – 2009). Phase IVa 5 mm 5 mm 2 Week Displacements Residual Displacements

  8. What Triggers Selection of Potential Transients? • Accelerations • Finite Strain • Analysis of finite strain tensor and displacement vector fields • Does signal look tectonic?

  9. Phase IVa Residual displacements  reference solution subtracted out

  10. Finite Displacements + Strain (principal axes) Phase IVa

  11. Phase IVb Residual displacements  reference solution subtracted out

  12. Phase IVb Finite Displacements + Strain (principal axes)

  13. Phase IVc Residual displacements  reference solution subtracted out

  14. Finite Displacements + Finite Strain (Principal Axes) Phase IVc

  15. Summary of results from Phase IV • The modeling of displacements with reference field removed captures spatial and temporal magnitudes of transients • Method can be automated

  16. Analysis of PBO Data from 2010.35 – 2011.25 • El Mayor-Cucapah post-seismic motions and strains • Non-steady state motions with periods of apparent increasing and decreasing strain • High frequency strain changes in LA Basin region

  17. Finite Strain (Dilatations) + displacements: PBO Data 2010.35 – 2011.25 See poster B-143

  18. Residual displacements show rapid spatially correlated changes in LA region 2010.35

More Related