新疆高砷地区地下水水化学特征及其成因分析

Hydro-chemical characteristics and the formations for groundwater in Kuitun,Xinjiang

以中国大陆第一个砷中毒病区新疆奎屯垦区为研究区域,测定了72份地下水水样中的主要化学离子,运用统计学、Piper三线图和Gibbs图等方法,分析了该地区地下水水化学特征及其成因。结果表明:该地区地下水为弱碱性、碱性的还原环境,地下水中As和F^-含量较高,呈极显著正相关。水化学类型主要为碱金属-重碳酸型,离子组成主要受蒸发岩风化和碳酸盐岩的控制。天山与河流沉积平原相结合的地质环境、强烈的蒸发浓缩作用使地下水中的砷得以富集,铁氧化物/氢氧化物还原过程可能是该地区导致固相砷的活化并向地下水中迁移和富集的主要原因。

Kuitun Farming Area in Xinjiang was the first area that had been identified with endemic arsenic poi- soning disease in China. 72 bottom groundwater samples were collected from Kuitun, and major ions in these samples were measured. Hydro - chemical characteristics of the groundwater and the formations were analyzed with statistics, Piper diagram and Gibbs diagram. The results showed： The groundwater was alkaline and strong reduction environment. The concentration of As and F- were high in groundwater. As. and F- had significant correlation. Alkalis metal - bicarbonate groundwater was the most dominant type. The chemical ions of groundw- ater were mainly affected by rock weathering and evaporation crystallization. Tianshan mountains, fluvial sedi- mentary plain and strong evaporation provided a favorable environment for the high arsenic groundwater. Ironox- ide/hydroxide reduction process might be the main cause of the activation and migration and enrichment of arse- nic in the region.