衡水地区高氟地下水化学特征及其成因

发布时间：2018-03-09 08:49

本文选题：衡水　切入点：地下水　出处：《中国地质大学(北京)》2015年硕士论文　论文类型：学位论文

【摘要】：氟元素是对于人体健康十分重要的一种微量元素,适量的摄入能在一定程度上预防龋齿的发生,但是氟摄入量过多时则会引起地方性氟中毒例如氟斑牙、氟骨病等病。论文的研究区为河北衡水地区,根据前人的研究经验进行野外踏勘、地下水样品的采集并进行分析和测试,综合分析衡水地区高氟地下水的水化学特征及其影响因素。本次研究中采集地下水样品62件,地表水样品1件,沉积物样品50件,沉积物孔隙水样品50件,检测分析了样品常量组分、同位素组分,经过研究得到的认识主要有:(1)浅层高氟地下水的水化学类型为Cl SO4 Na Mg,HCO3 Cl SO4 Na和SO4 Cl Na Mg型水;深层高氟水的水化学类型以HCO3 SO4 Cl Na和Cl SO4 Na型水为主。(2)氢氧同位素分析结果表明,浅层地下水主要以降水为补给来源,受到一定程度蒸发作用的影响。深层地下水氢氧同位素δD和δ18O值偏低,其组成与形成的环境条件有关,深层地下水年龄更大,是在较为寒冷的气候条件下形成的。碳同位素分析表明,水中的DIC来自岩石的风化溶解和生物降解有机物的混合。(3)高氟水主要分布在埋藏深度为50 m、200 m、300 m左右的含水层中。高氟水的水平分布特征与研究区地下水的补径排有关。高氟水主要分布在研究区东南部。(4)浅层和深层地下水绝大多数p H值集中在7-9之间,微碱性的环境更利于氟的富集。地下水中Na+与F-存在明显的正相关性。Ca2+、Mg2+的富集会抑制水中氟的富集。(5)决定衡水地区水化学特征的主要水文地球化学过程有:溶解-沉淀过程、蒸发浓缩过程、阳离子交换过程和吸附-解吸过程。高氟水的形成与其赋存和迁移的环境条件有关。浅层高氟地下水的形成原因主要受到蒸发浓缩过程的控制,而深层高氟地下水则主要是受到溶解-沉淀作用、阳离子交换、吸附-解吸作用控制。
[Abstract]:Fluorine is a very important trace element for human health. Proper intake of fluorine can prevent dental caries to a certain extent, but excessive intake of fluoride can lead to endemic fluorosis such as dental fluorosis. The research area of this paper is Hengshui area, Hebei Province. According to the previous research experience, the field survey is carried out, and the groundwater samples are collected, analyzed and tested. In this study, 62 samples of groundwater, 1 sample of surface water, 50 samples of sediment and 50 samples of sediment pore water were collected. The water chemical types of high fluorine groundwater in shallow layer are Cl ~ (2 +) SO4 ~ (3) SO4 ~ (3) SO4 ~ (+) Na and SO4 ~ (+) Cl ~ (+ +) Na ~ (+) mg type water. The hydrochemical types of deep water with high fluorine concentration are mainly composed of HCO3 SO4 and SO4 Na type water. The results of hydrogen and oxygen isotope analysis show that the main recharge source of shallow groundwater is precipitation. The values of hydrogen and oxygen isotopes 未 D and 未 18 O of deep groundwater are low, and their composition is related to the environmental conditions in which they are formed. It was formed in a colder climate. Carbon isotope analysis shows that, DIC in water comes from weathering dissolution of rocks and mixing of biodegradable organic matter.) High fluorine water mainly distributes in aquifer with a buried depth of about 50 m ~ 200 m ~ 300m. Horizontal distribution characteristics of high fluorine water and recharge diameter of groundwater in the study area. High fluorine water mainly distributes in the southeastern part of the study area. 4) most of the pH values of shallow and deep groundwater are between 7-9, The enrichment of Na and F- in groundwater can inhibit the enrichment of fluoride in water. The main hydrogeochemical processes that determine the chemical characteristics of hydrochemistry in Hengshui area are as follows: dissolved precipitation process, the main hydrogeochemical processes that determine the chemical characteristics of hydrochemistry in Hengshui area, such as the concentration of Na and F-, the accumulation of Ca 2 + mg 2, which can inhibit the enrichment of fluoride in water. Evaporation and concentration process, cation exchange process and adsorption-desorption process. The formation of high-fluorine water is related to the environmental conditions of its occurrence and migration. The formation of shallow high-fluorine groundwater is mainly controlled by evaporation and concentration process. The deep groundwater with high fluoride is mainly controlled by dissolution-precipitation, cation exchange, and adsorption-desorption.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P641.3

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