青岛胶州湾沉积物痕量元素黄铁矿化程度及其剖面类型  

Pyritization of Trace Elements in Sediments of the Jiaozhou Bay, Qingdao, China

作　　者：叶思源[1] 武强[1] 钟少军[2] 周永青[1] 鲁静[3] 

机构地区：[1]中国矿业大学资源开发工程系,北京100083 [2]中国科学院海洋研究所,山东青岛266071 [3]青岛海洋地质研究所,山东青岛266071

出　　处：《地球科学（中国地质大学学报）》2006年第2期175-181,共7页Earth Science-Journal of China University of Geosciences

基　　金：中国重点海岸带滨海环境地质调查与评价项目(No.12112010310402);青岛近海沉积环境与海上奥运比赛场海域地质调查研究项目(No.XM(2002)-22E).

摘　　要：为了探索青岛近海不同沉积环境下不同痕量元素的黄铁矿化规律,2003年5月潜水员潜入海底采集了4个不同沉积环境的未扰动柱样,并利用HuertaDiazandMorse(1990)连续提取技术测试分析了沉积物痕量金属的不同存在形式(活性态和黄铁矿结合态)在垂直剖面上的分布规律.结果表明:除了在涨潮三角洲上部沉积和潮下带沉积物柱子的Cd和Cr外,痕量元素的黄铁矿化度的增高取决于其相应剖面上的DOP的增高;并且不同痕量元素向黄铁矿中转移的规模存在着较大的差别,即元素As、Hg和Mo转移的规模最大,Cu、Zn、Cd、Cr、Co和Ni中等,Pb和Mn最小;此外,还进一步揭示了河流三角洲沉积物的下部各元素的黄铁矿化程度高,而潮下带沉积物以及涨潮三角洲沉积物低.最后指出在河口水下三角洲进行的清淤工作应注意黄铁矿结合态痕量元素的活化而产生生物有效的毒性元素.To determine the pyritization characteristics of reactive trace elements in different anoxic marine sediments, 4 undisturbed cores were sampled by a diver in May 2003. The chemical speciations of the trace elements versus depth were performed using modified sequential extraction procedures from Huerta-Diaz and Morse （1990）. Results indicate that the degree of trace metal pyritization （DTMP） of most trace metals increased with increasing DOP. However, for As, Hg and Mo, the DTMP/DOP values were generally above the 1 ： 1 ratio line irrespective of the type of sedimentary environment involved, whereas the transition metals Cu, Zn, CA, Cr, Co and Ni displayed a close to linear increase in DTMP with DOP and moderate incorporation into pyrite. Pb and Mn were also gradually incorporated into the pyrite phase but without reaching the DTMP levels exhibited by the above metals. These results are consistent with the chemical attributes of these different classes of trace dements. Availability of organic matter content and sedimentary rate are apparently important factors controlling the incorporation of Cu, Zn, Co, Ni, Cr, CA and Mn into pyrite in Jiaozhou Bay. The authors conclude that special attention must be paid to during dredging activities to protect the pyrite fraction from being oxidized, especially where activity is carried out down to 20 cm in fiver delta sediments.

关 键 词：沉积物 活性态元素 黄铁矿结合态元素 黄铁矿化度 青岛胶州湾 

分 类 号：P59[天文地球—地球化学]