Research On The Enrichment Rule Of Fluorine Ion Concentration In Quaternary Groundwater Of Beijing South East Area

The study area is located in the downstream of Beijing City,a water shortage is particularly serious. But the concentration of fluorine in groundwater exceed the standard is a common phenomenon.In this paper, according to the hydrogeological survey in Beijing City, Southeast of the Quaternary water wells, in the full collection of local geographical data base, combined with the local renovation project a table of stratified pumping test, enrichment of the study area in the Quaternary Groundwater fluoride was studied, the main research results are as follows:(1) Distribution of fluoride in groundwater in Beijing city in the southeast of the Quaternary in the horizontal direction is found out: the study area of Q uaternary shallow groundwater fluoride concentrations exceed the standard in the horizontal direction are mainly distributed in Tongzhou District Town, Western and Eastern Majuqiao, Zhangjiawan house, Yongle Town in northern parts of Daxing District, Yufa town Department, Ding Zhen Lixian town and part of the region, the eldest son of town southeast and Caiyu town in most areas. The whole study area in shallow groundwater fluoride exceed the standard area of about 400km2, accounting for about 20% of the total study area. Study in the northeast area of deep groundwater in Quaternary fluoride concentrations exceed the standard southern region in the horizontal direction are mainly distributed in the eastern region of Tongzhou District West Town, Lucheng town and Mi Zi Zhen, in addition to the scattered Daxing District Weishanzhuang Town, town yufazhen a bit like eldest son and the fluoride area exceed the standard deep the Q uaternary Groundwater in about 100km2, accounting for about 5% of the entire study area.(2) distribution of fluoride in groundwater in Beijing city in the southeast of the Quaternary in the vertical direction has been found out: positive correlation between concentration and depth of groundwater in the Q uaternary aquifer area fluoride Mi Zi Dian West set: aquifer is more deep, the concentration of fluorine ions in groundwater is higher; on the other hand, fluorine ion concentration the groundwater in the lower. Taiwan Lake area concentration of Shallow Q uaternary Groundwater in groundwater fluoride exceed the st andard, and the fluoride concentration of deep groundwater and aquifer depth had no obvious correlation. Yongle store concentration of shallow groundwater in Q uaternary Groundwater-Caiyu area of fluorine ions increased fluoride concentration exceed the s tandard, the deep groundwater with aquifer depth and increasing trend. Weishanzhuang area of fluorine ion concentration in groundwater with aquifer depth changes, well depth is more than 200 m, kill more than 100 m, the concentration of fluorine in groundwater with aquifer depth increases with increase in fluoride exceed the standard great possibility. Lixian- diazepam- fluoride concentration in groundwater with aquifer depth area Yufa changes obviously, the fluoride concentration in the shallow groundwater with aquifer depth decreases with increasing trend, a planar distribution of fluoride in shal ow groundwater exceed the standard.(3) on the southeast of the Quaternary in Beijing groundwater fluoride enrichment mechanism: the distribution characteristics of groundwater in the study area, the p H value of calcium and sodium ions are conducive to the enrichment of fluorine ions, caused by fluoride ion concentration; Quaternary bedrock for the Jixian County Department of thewumlshan area, due to the bedrock water the fluorine ion concentration of 7-9mg/L, when the thickness of quaternary system is small, easy access to the Q uaternary bedrock water caused by water, deep groundwater in Quaternary fluoride enrichment; the study area is located in the large area o f fluorine ion enrichment basic structure or near fault. Deep geothermal water easily through these channels into the Q uaternary aquifer, caused by fluoride concentrations exceed the standard; the study area is flat, the groundwater flow is slow, the water carrying material easily deposited. With the Q uaternary lithology mainly is fine sand, clay and other fine particles, strong adsorption for substances in groundwater. In addition, the local climate is far greater than the evaporation of rainfall, evaporat ion and concentration has effect on groundwater in substance, these factors have caused the accumulation of fluoride ion in groundwater;The results of this study in the southeastern city of Beijing to prevent future quaternary concentration fluoride wells exceed the standard, improve the success rate of the Quaternary water well construction, has important significance in saving water wel s transformation funds.