An analysis of the temporal and spatial gathering and dispersion patterns of crowds at the community level after the 2020 M5.1 Tangshan Guye earthquake

Abstract An accurate analysis of post-earthquake crowd movements at a community level can produce a detailed data basis to aid the government in its emergency response and management efforts, as well as can provide a relatively accurate basis for evaluating disaster relief operations and the restoration of social order in a timely fashion. A magnitude-5.1 earthquake occurred in Tangshan, Hebei, China on July 12, 2020. In this study, population densities were quantified at various temporal and spatial scales based on 4.29 million mobile phone location records collected after this earthquake using different bandwidths selected for kernel density estimation in different areas. The proportions of the destinations of the crowd movements in typical areas near the epicentre were determined. The results show that the majority of the people sought shelter within their communities and that people gathered and dispersed basically within 30 min. This study summarizes community-level movement patterns among shelter-seeking residents following nondestructive earthquakes and gives a quantitative basis for establishing shelters at various levels.