Research on the Problems of Land Subsidence in China

The land subsidence in China can be divided into two types: (1) the subsidence mainly caused by excessive groundwater withdrawal; (2) the subsidence caused by groundwater, oil, gas and warm groundwater withdrawal, and superposing on the neotectonic movement. Not only the different layers have different deformation features, but also the same layers in different locations have different deformation features. Even in the same location the same layers have different features in different stage. The corresponding models based on the actual deformation features of the soil should be built in order to simulate the real subsidence condition. The coupling of the models and the difference between vertical and horizontal scales are the problems to be solved for the accurate simulation.