Universal precursor seismicity pattern before locked-segment rupture and evolutionary rule for landmark earthquakes

• Published in: 地学前缘（英文版） Vol. 13; no. 3; pp. 22 - 34
• Main Authors: Hongran Chen, Siqing Qin, Lei Xue, Baicun Yang, Ke Zhang
• Format: Journal Article
• Language: English
• Published: Innovation Academy for Earth Science,CAS,China 2022; Key Laboratory of Shale Gas and Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,China; College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,China%School of Resources and Civil Engineering,Northeastern University,China; Innovation Academy for Earth Science,CAS,China%Key Laboratory of Shale Gas and Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,China
• Subjects: Peak-stress point; Landmark earthquake; Precursor; Locked segment; Volume-expansion point
• ISSN: 1674-9871

Despite extensive investigations,no precursor patterns for reliably predicting major earthquakes have thus far been identified.Seismogenic locked segments that can accumulate adequate strain energy to cause major earthquakes are highly heterogeneous and low brittle.The progressive cracking of the locked segments with these properties can produce an interesting seismic phenomenon:a landmark earthquake and a sequence of smaller subsequent earthquakes(pre-shocks)always arise prior to another landmark earthquake within a well-defined seismic zone and its current seismic period.Applying a mechanical model,magnitude constraint conditions,and case study data of 62 worldwide seismic zones,we show that two adjacent landmark earthquakes reliably occur at the volume-expansion point and peak-stress point(rupture)of a locked segment;thus,the former is an identified precursor for the latter.Such a pre-cursor seismicity pattern before the locked-segment rupture has definite physical meanings,and it is uni-versal regardless of the focal depth.Because the evolution of landmark earthquakes follows a deterministic rule described by the model,they are predictable.The results of this study lay a firm phys-ical foundation for reliably predicting the occurrence of future landmark earthquakes in a seismic zone and can greatly improve our understanding of earthquake generation mechanism.