成都市红层地下水水化学特征及污染成因研究

发布时间：2018-04-22 21:15

本文选题：水化学特征 + 污染现状评价　；参考：《成都理工大学》2015年硕士论文

【摘要】：成都是我国重要的商品粮生产基地,也是四川人口最稠密、经济最发达的地区。成都市总面积12121平方公里,红层区面积达4200km2,占全市面积近1/3,覆盖11个区(市)县的94个乡(镇)。然而在成都红层地区,由于地质以及水文、气象等因素的影响,水土涵养条件差,水资源短缺,地下水是该区的主要水源之一。因此深入研究成都红层区地下水的水化学特征,水文地球化学成因,污染现状及污染成因对成都红层地区地下水合理开发及可持续利用具有重要意义。本次研究以成都市红层丘陵区为研究区,以地下水系统理论为指导,以野外水文地质调查和水样采取为基础,综合运用水文地质学、水文地球化学等原理,采用定性分析和定量计算相结合的方法,开展了成都市红层地下水化学特征及污染成因的研究。得出以下几点认识:1、成都红层地区浅层地下水的水化学类型以HCO3-Ca和HCO3-Ca?Mg型水为主,所采集水样中也存在HCO3?SO4-Ca及HCO3?SO4-Na两种水化学类型。风化裂隙水、层间承压水及溶蚀孔洞水三类地下水水化学类型较为相似均以HCO3-Ca或HCO3-Ca?Mg型水为主。2、以本区环境背景值的上限和《地下水质量标准》中的三类水的水质指标为参考对照,利用单指标污染指数评价法对本区的地下水污染现状进行了评价。评价结果表明研究区地下水污染主要集中于崇州市、大邑县、浦江县、新都区、青白江区及金堂县等地,成都红层区其余县市均为未污染地区或轻度污染地区。3、利用PHREEQC软件对殷家沟小流域地下水演化过程进行了模拟,模拟结果表明导致小流域水化学组分发生变化的主要化学过程为方解石、白云石、石膏的沉淀作用,石英的溶解作用,CO2的溢出以及阳离子交换反应。4、通过MODFLOW对殷家沟小流域污染物的迁移模拟发现污染的迁移范围较小且污染物的浓度变化呈现周期性的变化规律。
[Abstract]:Chengdu is an important commodity grain production base in China. It is also the most densely populated and economically developed area in Sichuan. Chengdu has a total area of 12121 square kilometers and a red layer area of 4200 km2, accounting for nearly one third of the city's total area, covering 94 townships (towns) in 11 districts (cities) and counties. However, due to the influence of geology, hydrology, meteorology and other factors, soil and water conservation conditions are poor, water resources are short, and groundwater is one of the main water sources in the red bed area of Chengdu. Therefore, it is of great significance to study the hydrochemical characteristics, hydrogeochemical causes, pollution status and pollution causes of groundwater in the red bed area of Chengdu for the rational development and sustainable utilization of groundwater in the red bed area of Chengdu. This study takes the red bed hilly area of Chengdu as the research area, takes the theory of groundwater system as the guidance, takes the field hydrogeology survey and the water sample adoption as the foundation, synthetically applies the principles of hydrogeology, hydrogeochemistry and so on. By combining qualitative analysis with quantitative calculation, the chemical characteristics and pollution causes of red bed groundwater in Chengdu were studied. It is found that the main hydrochemical types of shallow groundwater in the red bed area of Chengdu are HCO3-Ca and HCO3-Ca?Mg type water, and HCO3?SO4-Ca and HCO3?SO4-Na are also found in the collected water samples. Weathered fissure water, The chemical types of groundwater in interlayer confined water and dissolved pore water are similar to each other in HCO3-Ca or HCO3-Ca?Mg type water. The upper limit of environmental background value in this area and the water quality index of three types of groundwater in groundwater quality Standard are taken as reference control. The present situation of groundwater pollution in this area was evaluated by single index pollution index method. The results show that groundwater pollution is mainly concentrated in Chongzhou City, Dayi County, Pujiang County, Xindu District, Qingbaijiang District and Jintang County. The other counties and cities in the red bed area of Chengdu are non-polluted areas or mildly polluted areas. The evolution process of groundwater in Yinjiagou small watershed is simulated by PHREEQC software. The simulation results show that the main chemical processes leading to the change of the chemical composition of water in the small watershed are the precipitation of calcite, dolomite and gypsum. The CO _ 2 spillover and cation exchange reaction of quartz. Through the simulation of pollutant migration in Yinjiagou small watershed by MODFLOW, it is found that the range of pollution migration is small and the concentration of pollutants changes periodically.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X523

【引证文献】