1 / 17

On modeling induced seismicity

On modeling induced seismicity. Flaminia Catalli. with. Valentin Gischig Men-Andrin Meier Stefan Wiemer. Sebastian Hainzl Torsten Dahm. First Story : earthquake interactions, the Basel case and a stochastic model. A). C). Catalli et al., GRL (2013). D). B).

igeary
Download Presentation

On modeling induced seismicity

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. On modeling induced seismicity Flaminia Catalli with Valentin Gischig Men-Andrin Meier Stefan Wiemer Sebastian Hainzl Torsten Dahm

  2. First Story : earthquake interactions,the Basel case and a stochastic model

  3. A) C) Catalli et al., GRL (2013) D) B)

  4. Geomechanical stochastic seed model Gischig and Wiemer, GJI (2013) • Can we reproduce the CI observed behavior? • How considering event interactions may improve a PSHA?

  5. A) • Potential earthquakes (seeds) uniformly random distributed over modeling area • Differential stressestimate from in-situ stress field • Mohr-Coulomb failure criterion assuming θ optimally oriented • Local b-value and magnitude • EQ interactions • Retriggeringstress-drop, DCFS and a new stress state are assigned to all seeds B) Goertz-Allmann and Wiemer, Geophys. (2013)

  6. P DCFSint P+DCFSint t=3days t=5days t=7days

  7. injection+interactions injection only

  8. Still an open question DCFSp DCFSint

  9. Conclusions #1 : • Interaction Coulomb stress changes may improve the spatial assessment of induced seismicity • We need a robust null hypothesis to confirm the validity of the CI time-distance behavior • Do we maybe need a more realistic hypocenter distribution considering fractal clustering?

  10. Second Story : Rate-and-state effect of pore-pressure diffusion on induced seismicity

  11. Linear pressure diffusion equation

  12. Rate-and-state model no perturbation stressing rate change sudden stress change Toda et al. Nature (2002)

  13. D = 0.05 m2/sec radius of the source = 1 m

  14. Conclusions #2 : • Rate-and-state does not have a tuning parameter to fit the total number of events without providing physical reasons • Rate-and-state based predictions are very sensitive to the pressure model or to local variations of the background

More Related