Delimitation Of Water Levels Under Different Types Of Study Areas

Groundwater resources are an important part of water resources,an important natural resource to support the healthy development of economy and society,and also an important factor that constitutes and affects the ecological environment.The groundwater level is a comprehensive reflection of various hydrological factors.It not only reflects the comprehensive change law of groundwater recharge,runoff,and drainage conditions,but also is an important indicator that can be used to judge environmental geological problems occur and their severity.The change of groundwater level is not only the most direct manifestation of the amount of groundwater resources,but also the most important control indicator in the process of groundwater management.Based on the analysis of relevant data on groundwater management and control at home and abroad,this paper redefines the concept of groundwater management and control water level,and classifies groundwater management and control water level.According to the characteristics of groundwater development and utilization and environmental geological problems caused by groundwater development and utilization,different types of groundwater management and control water levels are delineated.According to the characteristics of different types of areas,typical research areas were selected,and through appropriate delineation methods,the delineation research work of groundwater management and control water levels in different types of areas was completed.The main research contents and conclusions of this paper are as follows:This thesis defines the concept of groundwater management and control of water level.According to the characteristics of groundwater development and utilization and environmental geological problems caused by groundwater development and utilization,different types of groundwater management and control water levels are divided into shallow groundwater type areas,deep confined water type areas,and key research types Area.According to the selection principles of typical research areas,typical research areas of different types are selected.According to the characteristics of groundwater mining in typical research areas,the method of groundwater management and control in typical research areas is selected to delineate and combined with the characteristics of typical research areas for improvement.Taking the shallow groundwater level in Puyang as a typical research area for shallow groundwater type areas,the water balance method,dredging volume method,and time series method are used to delimit the groundwater management and control water level in the typical research area.At the same time,the rationality of the calculation results is analyzed in combination with the changing characteristics and management objectives of shallow groundwater levels in the study area.Through the comparison of the demarcation results of three methods,the rationality and applicable conditions of delimiting groundwater management and control water level by each method are analyzed.Among the three demarcation methods,the water balance method takes into account both the years of different rainfall levels and the division of hydrogeological conditions.The delineation results of groundwater management control water levels are most applicable.Taking the urban water source area of Xiping County,Henan Province as a typical research area,a set of delineation methods for confined water management and control of water levels was constructed.By collecting the groundwater level change data,hydrogeological data,and borehole data in the study area,the hydrogeological conceptual model and groundwater numerical model were established to obtain the change of the confined water level at different mining intensities within the study area.The model calculates the magnitude of the water level drop under different mining intensities within the study area and draws a contour map of the water level drop.According to the principle of delineation of the control water level of the confined water management,the results of the model are combined with the boundaries of the protection zone of the delineated water source area to delineate the water level of the confined water management and control,and make a rational analysis of the delineation results.Taking G06 typical observation wells as an example,the restricted water level is 22.25 m,the prohibited water level is 17.78 m,and the deep confined water management control water level threshold range is 17.78?22.25 m.Taking the land subsidence area in Luoyang urban area as a typical research area,through the analysis of the mechanism of land subsidence,the relationship between the groundwater level and the ground subsidence in each subsidence area of the research area is analyzed.Then,the empirical formula method is applicable to calculate the land subsidence in the study area.By establishing a numerical model of groundwater in the study area,the model predicts the future change of groundwater level in the study area,and then uses the empirical formula method to calculate the land subsidence in the study area.According to the delineation principle of groundwater management and control water level in the ground subsidence area of the study area,the groundwater management and control water level of the study area is demarcated,and the demarcation results are reasonably analyzed.Taking Luonan Water Source Settlement Center as an example,the restricted mining water level is 126.34 m,the prohibited mining water level is 119.99 m,and the groundwater management control water level is 119.99 ? 126.34 m.