Reginal crustal stability evaluation in Zhuhai city based on GIS platform

Objectives Regional crustal stability is an important foundation for geological safety and plays a fundamental role in urban planning, engineering construction, disaster prevention and mitigation. Zhuhai City in Guangdong Province is the only city in the mainland that is connected to Hong Kong and Macao by land bridge, with high population density and prone to geological disasters, but there is a lack of research on regional crustal stability in this area. Methods In order to carry out the evaluation of regional crustal stability in Zhuhai, based on the field investigation and extensive data collection, the influencing factors and characteristics that control and affect the regional crustal stability were analyzed, and eight evaluation indexes were selected, such as deep geophysics, seismicity, peak seismic acceleration, crustal deformation, fault activity, modern tectonic stress field, rock and soil structure and characteristics, and geologic hazard conditions, and the indexes were classified and assigned values. Based on the GIS platform, a multi-factor weighted superposition analysis method was adopted to establish a comprehensive evaluation model and quantitative evaluation of the regional crustal stability through the evaluation of tectonic stability, geotechnical stability and ground stability. Results The study area was classified into four grades, namely, stable area (31.38%), sub-stable area (58.32%), sub-instable area (9.8%) and unstable area (0.5%). Conclusions Based on these results, we proposed avoidance measures and suggestions for urban planning and construction, providing a scientific basis and response strategies for future land space planning, engineering construction, and disaster prevention and mitigation in Zhuhai City.