【作者】 徐争启；

【导师】 倪师军； 张成江；

【作者基本信息】 成都理工大学 ， 地球化学， 2005， 硕士

【摘要】 本论文从攀枝花市区水系沉积物入手,详细研究了攀枝花市东到金江车站、西到格里坪长约四十公里范围内的金沙江及其支流水体的物理化学性质及水系沉积物中重金属的地球化学特征。重点调查研究了攀枝花市区水体的物理化学性质、水系沉积物的组成、水系沉积物中重金属的分布以及形态特征,应用当前国际上较为先进的评价沉积物环境污染状况的方法对攀枝花市区水系沉积物中的重金属污染程度进行了评价。在上述研究的基础上,分析了攀枝花市区地表水环境的污染原因、提出了防治污染的对策建议。取得的创新性成果及认识如下: (1) 采用X射线衍射及扫描电镜分析了水系沉积物的粒度及组成。攀枝花市区水系沉积物颗粒呈不规则状,棱角明显,磨圆度差;水系沉积物的矿物组成以石英为主,粘土矿物次之,含量依次为:石英>伊利石>绿泥石>方解石>长石;细粒样品中的粘土矿物高于粗粒样品。水系沉积物的组成以自然风化冲刷物为主,同时夹杂有人为的工业活动产物。 (2) 详细研究了水系沉积物中重金属的空间分布特征。重金属的高含量区主要分布在攀钢到选矿厂、尾矿坝的中游地区;支流含量普遍高于干流,支流对干流有重要的影响;剖面上,大部分重金属含量上层高于底层。 (3) 研究了重金属在不同粒度样品中的分布特征。发现除钒外,所有元素的含量都是细粒样品高于粗粒样品;两种样品重金属之间呈强相关性。 (4) 分析了重金属的相互关系。发现重金属除Pb、Zn外,其它元素之间呈较明显的正相关。聚类分析表明重金属的类型为Ti-V-As-Cu-Co-Cr-Mn、Pb-zn型;而因子分析表明重金属的来源与基性—超基性岩等岩石背景有关。 (5) 采用连续提取法分析了重金属的形态特征。研究发现各重金属的形态以残渣态为主,离子交换态含量很少;各元素的形态有自己的特点。铜在有机物和硫化物结合态中的含量较高,钴在碳酸盐结合态中的含量较高,铅锌钴的铁锰氧化物结合态较高;在空间分布上,各形态在中游变化较大,可能是受到工业活动影响。 (6) 应用当前国际上较为先进的评价沉积物环境污染状况的方法,采用两种评价标准三种评价方法对攀枝花市区水系沉积物中的重金属污染程度进行了评价。结果发现金沙江标准的评价结果略高于全球页岩标准结果;从评价结果来看,总体上评价结果是一致的,即攀枝花市区水系沉积物中重金属的污染程度较轻,属于轻度—中度污染。 (7) 较深入地研究了重金属的污染来源。认为攀枝花市区水系沉积物中的重金属污染源主要由沿江工矿企业排放的废水引起,同时攀枝花市的高地质背景值也是水系沉积物中重金属含量增高的原因之一。最后提出了水环境防治的对策建议。更多还原

【Abstract】 This thesis starts with sediments in Panzhihua downtown area, and focuses not only on the physical chemistry characteristics of Jinsha River and its branches within a range of about 40km in Panzhihua City, which is from Jinjiang Station on the east and to Geliping on the west, but also on the geochemical characteristics of heavy metals in sediments. In the thesis, the author uses geochemical methods to study heavy metals in sediments in Panzhihua downtown area from the angle of environment and gets some creative achievements. They are:(1) Using X-ray diffraction and scanning electrical mirror to analyze the grain size and components of sediments. The mineral in sediments consists mainly of quartz, second to which is clay mineral. The sediment exists in the form of mineral aggregate and looks irregular, having obvious edges and corners; the sediment is constituted mainly of naturally weathered and eroded material, together with artificial products caused by industrial activities.(2) Study the space distribution characteristics of heavy metals in sediment. Heavy metals’ contents are the highest in the middle reaches of the river; their contents in branch are generally higher than in the trunk stream; branches have great influence on the trunk stream; on the profile, most heavy metals have higher contents on upper levels than at the bottom.(3) Study the heavy metals’ distribution characteristics in different granularity samples. It is found that, except V, all elements have higher contents in fine grain samples than in coarse grain samples; heavy metals in the two samples have strong correlation.(4) Analyze the correlation between heavy metals. It is found that there is a comparatively obvious positive correlation between elements, except Pb and Zn. Clustering analysis shows that the type of heavy metals is Ti-V-As-Cu-Co-Cr-Mn, Pb-Zn Type; while factor analysis shows that the source of heavy metals is related to rock backgrounds such as basic-superbasic rock.(5) Using continually extraction to analyze the speciation characteristics of heavy metals. It is found that heavy metals mainly exist in residua, while the content of ion exchange is very low; all elements’ speciations are different. In space distribution, all speciations change greatly in the middle reaches of the river, which might be influenced by industrial activities.(6) Using three advanced methods and two standards to evaluate the pollution caused by heavy metals in sediments in Panzhihua downtown area. It is found that the evaluated results for Jinshajiang standard are a little higher that those for global shale standard; from the results of three different evaluating methods, it can be found that the general evaluated results are identical, that is, the pollution caused by heavy metals in sediments in Panzhihua downtown area is lighter, belonging to light-medium pollution.(7) Analyze the source of heavy metals that cause pollution. The author thinks that the heavy metals in sediments are mainly caused by waste water discharged from factories along the river. Meanwhile, high geological background of Panzhihua City is another reason for high content of heavy metals in sediments. At the end of the thesis, the author also puts forward some countermeasures and suggestions for protecting water environment.更多还原