How does fault strike change along strike-slip ruptures? A comparison between fault segments and their regional stress field
Vanessa Herrera
BS Candidate
Advisor: Dr. Jillian Maloney
Friday, May 4, 2023
11 am in CSL 422
watch Vanessa’s talk
Abstract
Earthquake gates, such as fault bends, can inhibit rupture propagation and thus exert a primary control on rupture length, and consequently, the final size of the earthquake. Therefore, investigating the mechanics of rupture propagation through bends is important for better constraining seismic hazard and potential earthquake magnitude maxima. Through analysis of geometrical and stress characteristics of thirty-one strike-slip earthquakes using the Fault Displacement Hazard Initiative (FDHI) surface rupture database, we revisit the strength of fault bends by looking at their orientations with respect to the regional stress field and other segments along the rupture. We simplified each rupture map into linked segments, mapped at a scale of 1:50,000. We find most segments along a rupture are at 30-60 degree angles from the maximum compressive regional stress, shmax, consistent with the Mohr-Coulomb failure criterion. We find that most segments are at acute angles from their neighboring segments. Future work will involve investigating the strength of different segments of the rupture in the context of their regional stress field.