Earthquake Damage Patterns Resolve Complex Rupture Processes

Abstract

AbstractFracture damage patterns around faults induced by dynamic earthquake rupture are an invaluable record to clarify the rupture process on complex fault networks. The 2016 Mw 7.8 Kaikōura earthquake in New Zealand has been reported as one of the most complex earthquakes ever documented that ruptured at least 15 crustal faults. High‐resolution optical satellite image displacement maps provide distinctive profiles of displacement across the faults and help visualize the off‐fault damage pattern. They are combined with field observation and coupled with a numerical tool that captures the dynamics of the rupture and simultaneous activation of off‐fault damage to allow the determination of the most likely rupture scenario. This study demonstrates that complex rupture processes can be explained in a rather simple way via a synergetic combination of state‐of‐the‐art observation and first principle physics‐based numerical modeling of off‐fault damage.