Groundwater System Evolution And Genesis Of Relevant Environmental Problems: A Case Study At Taiyuan Basin, Shanxi Province, China

Taiyuan basin is a representative large-scale Cenozoic rift basin in Shanxi Province, northern China. During the later Cenozoic, the complex groundwater system in Quaternary sediments was formed in Taiyuan basin under the control of the basin's geological evolution process. Groundwater in porous media was not only the outcome of the combined actions of diversified geologic processes during certain geological time, but also one of the most active influential factors for the regional geological evolution process. So it can be regarded as the receptor and information carrier of the geological environment change. Furthermore, as one of the important components of regional water circulation, pore water can be used to indicate the extent of regional climate change and the scale of human activities in the basin. In the study area, the groundwater exploitation and other human activities with increasing intensity, such as mining, land utilization, construction of water conservancy works, and urbanization, had substantially changed the environment and the regional groundwater regime, and induced a series of correlative water resource-environmental problems such as regional groundwater level falling, urban land subsidence, and groundwater pollution. Analyzing the genesis of these environmental problems depends on the research on the occurrence, flow path and geochemical evolution of pore water in the basin. Thus, in order to well understand the above characteristics of pore water, the evolution process of the pore water system in Taiyuan basin controlled by regional tectonic movement, climate change and human activities was discussed and the spatial structure of the porous matrix was analyzed. The results of the study are both theoretically and practically important.Understanding groundwater evolution process and groundwater system structure is usually the basis of analyzing the genesis of groundwater environment problems. In this thesis, efforts were made to study the geological evolution process and subsurface pore media structure of Taiyuan basin, so as to understand the general temporal-spatial pattern of the pore water system in the basin. Firstly, the morphology of the basement surface, the Quaternary stratum base morphology, and the modern geomorphy of the basin were plotted using geophysical data and...