Three-Dimension Finite Element Numerical Simulation On Geothermal Water And Land Subsidence Research Of Geothermal Area In FuZhou

On the basis of the analysis of the topography, geomorphology, geological structure of geothermal area and surroundings in Fuzhou city, and the survey of hydrogeological condition, and the distribution of geothermal drilling, and the geothermal water exploitation, and the groundwater regime, and the scale and distribution of land subsidence, the relationship between land subsidence and geothermal water regime was discussed. The result showed that land subsidence of geothermal area in Fuzhou city was mainly induced by the excessive extraction of geothermal water in the thesis. Through summarization for complicated geohydrology and engineering geology condition of research area, the non-stability 3-Dimension flow model of ground water and land subsidence model were established in this thesis. The coupled models of ground water and land subsidence were combined with a large series of water level observation and land subsidence information to debug the parameters and ascertain the models. The models can simulate the regulation of the groundwater level and land subsidence and reveal the characteristic of land subsidence in Fuzhou. With IDL (Interactive Data Language) designed by America RSI Co., a 3D Visualization model of land subsidence was implemented.Simultaneously, according to observed record of land subsidence and geological data, a gray system model of land subsidence was established. This model can predict land subsidence of geothermal area in Fuzhou city.The measures of prevention for the special geological background of the production and development of the geothermal area resources were also given.The results are of great practical significance on the efficient development of geothermal water and the control of land subsidence in practice. The models can also be applied to the areas with homologous hydrogeological condition.