Spatiotemporal Analysis of Earthquake Distribution and Associated Losses in Chinese Mainland from 1949 to 2021

Abstract

A comprehensive earthquake hazard database is crucial for comprehending the characteristics of earthquake-related losses and establishing accurate loss prediction models. In this study, we compiled the earthquake events that have caused losses since 1949, and established and shared a database of earthquake hazard information for the Chinese mainland from 1949 to 2021. On this basis, we preliminarily analyzed the spatiotemporal distribution characteristics of 608 earthquake events and the associated losses. The results show the following: (1) The number of earthquakes is generally increasing, with an average of annual occurrence rising from three to twelve, and the rise in the economic losses is not significant. The number of earthquakes occurring in the summer is slightly higher than that in the other three seasons. (2) The average depths of earthquakes within the six blocks display a decreasing trend from west to east, with a majority (63.8%) of earthquakes occurring at depths ranging from 5 to 16 km. (3) Although the number of earthquakes in the east is lower than that in the west, earthquakes in the east are more likely to cause casualties when they have the same epicenter intensity. Southwest China is located in the Circum-Pacific seismic zone where earthquake hazards are highly frequent. The results can provide fundamental data for developing earthquake-related loss prediction models.