Supershear cascading rupture envelopes: a case study from the 2023 Kahramanmaraş seismic doublet


Zaccagnino D., Stabile T. A., Akinci A., Herrero A., TAN O., Telesca L., ...Daha Fazla

FRONTIERS IN EARTH SCIENCE, cilt.13, 2025 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 13
  • Basım Tarihi: 2025
  • Doi Numarası: 10.3389/feart.2025.1683922
  • Dergi Adı: FRONTIERS IN EARTH SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Geobase, INSPEC, Directory of Open Access Journals
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Hayır

Özet

Super-shear ruptures, characterized by velocities exceeding the shear wave speed, were first predicted theoretically and later observed in laboratory experiments. While a few tectonic earthquakes have been reported as super-shear, most involve strike-slip faults, including the 2023 Mw 7.5 Kahramanmara & scedil; earthquake (T & uuml;rkiye) and transient phases of the Mw 7.8 event. However, natural ruptures propagate through complex, rough fault systems - deviating from idealized smooth interfaces - resulting in heterogeneous slip, stress drops, and rupture jumps. Additionally, the expected high-frequency spectral signature of super-shear ruptures often conflicts with observations. To reconcile these discrepancies, we propose a generalized interpretation of super-shear events, where observed super-shear velocities arise not only from continuous rupture fronts but also from dynamically triggered multi-focal ruptures along strike. We explore how fault rheology modulates rupture speed and introduce a triggering mechanism driven by P-wave perturbations. Our model also predicts Mach cones detected teleseismically during super-shear earthquakes such as the Kahramanmara & scedil; doublet, while it suggests they should not be observed locally in the case of super-shear cascading rupture envelopes. We show that both the Kahramanmara & scedil; 2023 events initiated cascading instabilities, with dynamic stress transfers propagating rupture across fault patches. High-frequency (>10 Hz) P-wave pulses mark transitions between patches, identified via accelerometric waveform analysis. Our findings support the idea that even minor stress perturbations can trigger near-instantaneous dynamic ruptures, posing implications for early-warning algorithms.