Complex 3-D surface deformation in the 1971 San Fernando, California earthquake reveals static and dynamic controls on off-fault deformation
| dc.contributor.author | Gaudreau, É. | |
| dc.contributor.author | Hollingsworth, J. | |
| dc.contributor.author | Nissen, E. | |
| dc.contributor.author | Funning, G. J. | |
| dc.date.accessioned | 2024-03-05T23:01:03Z | |
| dc.date.available | 2024-03-05T23:01:03Z | |
| dc.date.issued | 2023 | |
| dc.description.abstract | The shallow 1971 MW 6.6 San Fernando, California earthquake involved a complex rupture process on an immature thrust fault with a non-planar geometry, and is notable for having a higher component of left-lateral surface slip than expected from seismic source models. We extract its 3-D coseismic surface displacement field from aerial stereo photographs and document the amount and width of the vertical and fault trace-parallel components of distributed deformation along strike. The results confirm the significant left-lateral surface offsets, suggesting a slip vector rotation at shallow depths. Comparing our offsets against field measurements of fault slip, we observe that most of the offset was accommodated in the damage zone, with off-fault deformation averaging 69% in both the fault trace-parallel and vertical components. However, the magnitude and width of off-fault deformation behave differently between the vertical and fault trace-parallel components, which, along with the rotation in rake near the surface, can be explained by dynamic rupture effects. | |
| dc.description.reviewstatus | Reviewed | |
| dc.description.scholarlevel | Faculty | |
| dc.description.sponsorship | E. G. was funded through an Alexander Graham Bell Canada Graduate Scholarship and Michael Smith Foreign Study Supplement from the Natural Sciences and Engineering Research Council of Canada, and a Montalbano Scholars Fellowship and President's Research Scholarship, both from University of Victoria. E. N. was supported by a Canada Research Chair and grants from the Natural Sciences and Engineering Research Council of Canada (NSERC Discovery Grant 2017-04029), the Canada Foundation for Innovation, and the BC Knowledge Development Fund. J.H. was supported by grants from CNES and BQR. G.F. was supported by SCEC Award 21128. | |
| dc.identifier.citation | Gaudreau, É., Hollingsworth, J., Nissen, E., & Funning, G. J. (2023). Complex 3‐D surface deformation in the 1971 San Fernando, California earthquake reveals static and dynamic controls on off‐fault deformation. Journal of Geophysical Research: Solid Earth, 128(3). https://doi.org/10.1029/2022jb024985 | |
| dc.identifier.uri | https://doi.org/10.1029/2022jb024985 | |
| dc.identifier.uri | https://hdl.handle.net/1828/16045 | |
| dc.language.iso | en | |
| dc.publisher | Journal of Geophysical Research: Solid Earth | |
| dc.rights | Attribution-NonCommercial 4.0 International | en |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc/4.0/ | |
| dc.subject.department | School of Earth and Ocean Sciences | |
| dc.title | Complex 3-D surface deformation in the 1971 San Fernando, California earthquake reveals static and dynamic controls on off-fault deformation | |
| dc.type | Article |