Study On The Model Of Land Subsidence In Cangzhou City

Land subsidence is an important problem. There is natural land subsidence, and also many human activities can induce several kinds of land subsidence hazards. Many kinds of human activities can induce land subsidence, such as groundwater withdrawal, mineral resources exploitation, building of skyscrapers and the exploitation of underground space. The land subsidence is very serious in Hebei plain of China, especially in Cangzhou city. In the region of Cangzhou city, the land subsidence has amounted up to 1131mm in 1990, and reached 2236mm in 2001.As the data says, the rate of land subsidence is very fast.Based on the actual hydrogeology and engineering geology condition of the area, a concept hydrogeological model is built first. Pumping from the confined aquifer, the clay stratum that is in and above the confined aquifer releases a large amount of water, resulting in the compaction of soil layer called land subsidence. Adjusting the hydrogeological parameters for many times and choosing the best ones. The Modular three-dimensional groundwater flow model--MODFLOW and another modular program-IBS are applied to simulate the water table and land subsidence synchronously and build the mathematical model of water exploitation-land subsidence. And based on this model a prediction of the situation of land subsidence is made up to 2015.Finally, some advices have been put forward for preventing the development of the land subsidence, such as looking for new water resources, strengthening administration, building the land subsidence measurement network and so on.