Objectives It is of important scientific significance for understanding the mechanism of strong earthquakes and evaluating the activity of strong earthquakes around the world.
Methods We collected the information on 198 strong earthquakes (Mw≥7.5) in the world from 1976 to early 2022, and statistically analyzed the temporal and spatial distribution of strong earthquakes and focal depth, and the proportion of strong earthquake types. Combined with the published typical strong earthquake interferometric synthetic aperture radar (InSAR) deformation map, we analyzed the spatial distribution characteristics of strong earthquake coseismic deformation.
Results The spatial distribution of strong earthquakes is banded, mainly located in the Pacific Rim seismic belt and the Himalayan-Mediterranean seismic belt. The time distribution of strong earthquakes has the phenomenon of alternating active periods and quiet periods. Most of the 198 earthquakes occurred in the ocean, and most of them are thrust fault earthquakes and shallow source earthquakes. The coseismic deformation of terrestrial strong earthquakes mainly focuses on the strip area near the two sides of the seismogenic fault. The farther away from the fault, the faster the deformation attenuation, and the deformation is asymmetrical about the fault.
Conclusions Since 1976, the activity of global strong earthquakes above Mw 7.5 shows an overall upward trend. The InSAR deformation field can present the spatial range and distribution characteristics of the coseismic deformation of strong earthquakes in detail. InSAR crustal deformation monitoring technology can be used to splice the deformation information fragments of active faults distributed in different locations around the world. It is possible to reveal the full-cycle seismogenic deformation process of strong land earthquakes.
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