Present situation of land subsidence and its mechanism in China

Present situation of land subsidence and its mechanism in China 

Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, China 

Keywords, land subsidence, deep groundwater, geological environment hazards, critical water level 

In China, severe subsidence is mainly distributed in the following regions the coastal plain area North-China Plain area coastal plain area in South-East China (including western coastal plain area of Taiwan Province) rift valley area of Fen-Wei Rivers. Large-scale subsidence is mainly detected in North-China plain and coastal plain areas. The most typical ones include Shanghai and Tianjin in the coastal plain area and Xi an city in Fen-Wei River plain area. The urban subsidence development process can be seen in Table 1. 

The annual subsidence rate in the following has exceeded 200 mm/a, namely, Xi an City in Shanxi Province, Pingdong City and Yunlin City in Taiwan Province. The largest annual subsidence rate in those cities once reached 300 mm/a. 

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