Abstract: The magnitude forecasting of strong earthquakes is of great scientific significance, and also plays an important role in the actual work of earthquake prevention and disaster reduction. Based on relevant research progress at home and abroad, this paper focuses on the identification of asperities and cascading ruptures in magnitude forecasting of strong earthquakes. The occurrence of earthquakes usually relates to the destruction of asperities. For the identification of asperities, comprehensive analysis can be carried out mainly from the aspects of the media nature in the seismogenic zone, small-medium seismicity, fault motion state, stress state, friction attribute, etc. The occurrence of cascading ruptures will increase the magnitude of earthquakes and the risk of earthquake disasters. The factors controlling its probability mainly include the geometric properties of faults, such as fault surface curvature, geometry change, step distance, as well as, the physical properties of fault and surrounding media, such as the friction properties of fault surfaces, changes in the width of seismogenic layer in adjacent fault segments, stress distribution of fault surfaces and shallow low-velocity fault zones. The research of relevant models and parameters depends on the development of intensive observation, fault exploration and other basic work, the application of numerical simulation, inversion and other technologies, and the integration of multiple disciplines. It is hoped that this paper can provide a reference for the forecasting of strong earthquake magnitude in key fault sections of the Chinese Mainland.

Key words: Asperity, Cascading rupture, Earthquake forecasting, Dynamic simulation