The Guangdong-Hong Kong-Macao Greater Bay Area, a world-class super metropolitan region consisting of nine cities in Guangdong Province and the two special administrative regions of Hong Kong and Macao, is highly sensitive to seismic geological hazards. Therefore, understanding the shallow subsurface structure of urban areas in the Greater Bay Area is of paramount importance for urban engineering construction, disaster prevention, and the development of underground spaces.
Using the spatial cross-correlation method, dispersion curves of Rayleigh waves were extracted from the microseismic signals recorded at observation points of short-period dense seismic arrays in the Greater Bay Area. The results indicated that the spatial cross-correlation method can effectively obtain stable and reliable shallow velocity structures beneath the observation arrays. Therefore, the combination of short-period dense seismic array technology and the spatial cross-correlation method is an effective, cost-efficient, and environmentally friendly means of conducting detailed subsurface structure investigations in densely populated urban areas. It will play a significant role in future shallow structure investigations in urban regions.