麦岭备用水源地地下水资源评价与合理开发利用研究

发布时间：2018-07-20 17:21

【摘要】：许昌市是我国严重缺水城市之一,水资源紧缺严重制约着城市的发展建设。麦岭水源地1993年正式向许昌市供水,缓解了许昌市严重缺水问题。2015年2月,许昌市南水北调配套工程正式通水,城市供水主要采用南水北调水源,麦岭水源地被规划为城市应急备用水源地。麦岭水源地处于埋藏型冲洪积扇(北汝河冲洪积平原)的中上游,地势平坦,根据含水层的结构特征,将含水层划分为浅层及深层。浅层水与深层水之间普遍存在2~12m厚的粉质黏土含姜石弱透水层,局部小于2m或大于15m,使二者水力联系密切,在开采条件下二者越流明显。深层含水层岩性为卵砾石层,厚度大,导水性和储水性好,调蓄能力强,是水源地的开采目的层。本文重点采用水均衡法和数值法计算评价地下水资源。根据水源地的水文地质模型,建立地下水均衡方程,计算了各补给量、排泄量和均衡差,并与计算的储存量变化量进行比较,其多年均衡误差均小于10%,说明所建立的均衡方程比较真实地反映了水源地的水文地质条件,所确定的各项水文地质参数合理可信。建立数学模型,运用Visual ModFlow软件进行数值模拟,利用长期观测的水位动态资料对模型进行识别和验证,建立地下水流数值模型。根据水源地水文地质条件和开采井布局,制定四种开发利用方案,并运用所建立的数值模型对四种开发利用方案的地下水位和流场进行预测,并对方案进行综合分析;分析结果表明开采井的布局及开采量的调控对水源地局部地下水位有较大的影响,优化方案能有效的防止水源地西部地下水位下降过快,有助于更充分的开发深层水资源,并且对浅层水的影响较小,避免与农业争水产生矛盾,有利于地下水资源的合理开发利用。
[Abstract]:Xuchang is one of the cities with serious water shortage, which restricts the development and construction of the city. The Meiling Water Source area officially supplied water to Xuchang City in 1993, which alleviated the serious water shortage in Xuchang City. In February 2015, Xuchang City's South-to-North Water diversion Project officially opened water, and the urban water supply mainly used South-to-North Water transfer Water Source. The Mailing water source area is planned as the emergency water source of the city. The mailing water source is located in the upper and middle reaches of the buried alluvial fan (North Ruhe alluvial plain) with a flat topography. According to the structural characteristics of the aquifer, the aquifer is divided into shallow and deep layers. There is a weak permeable layer of silty clay with a thickness of 212m between shallow water and deep water. The local area is less than 2m or more than 15m, which makes the hydraulic relationship between them close, and the overflowing between them is obvious under mining conditions. The lithology of the deep aquifer is a gravel layer with large thickness, good water conductivity and water storage, and strong regulating and storing capacity, so it is the target layer for exploitation of water source. In this paper, water balance method and numerical method are used to calculate and evaluate groundwater resources. According to the hydrogeological model of water source, the equilibrium equation of groundwater is established, and the recharge, discharge and equilibrium difference are calculated, and compared with the calculated variation of storage capacity. The multiyear equilibrium error is less than 10, which shows that the established equilibrium equation truly reflects the hydrogeological conditions of the water source, and the hydrogeological parameters determined are reasonable and reliable. The mathematical model is established, the numerical simulation is carried out by using Visual ModFlow software, and the model is identified and verified by using the dynamic data of water level observed for a long time, and the numerical model of groundwater flow is established. According to the hydrogeological conditions of water source and the layout of production wells, four development and utilization schemes are formulated, and the groundwater level and flow field of the four development and utilization schemes are forecasted by using the established numerical model, and the schemes are comprehensively analyzed. The analysis results show that the layout of production wells and the regulation of exploitation amount have great influence on the local groundwater level of the water source, and the optimization scheme can effectively prevent the groundwater level from falling too fast in the western part of the water source, which is helpful to the development of deep water resources more fully. And it has little influence on shallow water, avoiding contradiction with agricultural water competition, which is beneficial to the rational development and utilization of groundwater resources.
【学位授予单位】：华北水利水电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P641.8

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