开滦矿区煤伴生元素土壤地球化学分布模式及成因

摘要

Based on results from a multi-purpose regional geochemical survey in Hebei Plain,the geochemical distribution of the trace elements Se,Hg,Mo,Zn and U were found to be abnormal in the 0-20 cm topsoil of Kailuan coal mine,which has more than one hundred years' history of coal mining. Geochemical methods such as correlation analysis and multivariate-statistics were used to study soil geochemical distribution and genesis of the trace elements including Se,Hg,Mo,etc. in the topsoils. The results indicated that: 1 ) the anomalous area of soil trace elements dominated by Se was coincident with the boundary of the Kailuan coal mine; 2) the trace elements such as Se,Hg,Mo,etc. were enriched merely in the topsoils; and,3) Se in the soil was highly positively correlated with organic carbon (OC) and S,which are associated with coal in the coal mine with correlation coefficients of 0. 88 and 0.77 respectively. The dust spreading from coal mining and transportation,as well as soot from coal combustion,were the main causes of the abnormal accumulation of trace elements in the topsoils in the study area.%唐山开滦煤矿已有百余年的开采史.经河北平原多目标区域地球化学调查发现,Se、Hg、Mo、Zn和U等微量元素在矿区表层土壤(0～20 cm)中呈异常分布,故利用相关性分析、多元统计分析等地球化学方法,研究Se、Hg、Mo等微量元素土壤地球化学空间分布模式及其成因.结果表明:以Se元素为代表的土壤微量元素异常与煤田分布范围几乎一致,Se、Hg和Mo等微量元素只在表层土壤富集.土壤中Se与有机碳(OC)、S等煤炭伴生元素呈高度正相关,R(相关系数)分别为0.88和0.77.煤炭开采、运输产生的扬尘以及燃煤产生的烟尘是形成Se、Hg等微量元素表层土壤异常分布的主要原因.