预处理对海洋黏土矿物XRD测试结果的影响  

The Influence of Pretreatment on the XRD Analysis Results of Clay Minerals in Marine Sediment

作　　者：王颖[1,2] 乔淑卿 葛晨东[1] 石学法 方习生[2,3,4] 董智[1,2] WANG Ying;QIAO Shu-qing;GE Chen-dong;SHI Xue-fa;FANG Xi-sheng;DONG Zhi(Key Laboratory of Coast and Island Development,Ministry of Education,Nanjing University,Nanjing 210023,China;The First Institute of Oceanography,SOA ,Qingdao 266061,China;Key Laboratory of Marine Sedimentology and Environment Geology,SOA,Qingdao 266061,China;Laboratory for Marine Geology,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266061,China)

机构地区：[1]南京大学海岸与海岛开发教育部重点实验室,江苏南京210023 [2]国家海洋局第一海洋研究所,山东青岛266061 [3]海洋沉积与环境地质国家海洋局重点实验室,山东青岛266061 [4]青岛海洋科学与技术国家实验室海洋地质过程与环境功能实验室,山东青岛266061

出　　处：《海洋科学进展》2018年第2期242-252,共11页Advances in Marine Science

基　　金：国家海洋局国际合作项目--东南亚海岸带脆弱性合作调查研究和亚洲大陆边缘"源-汇"过程与陆海相互作用(GASIGEOGE-03)和马来半岛海岸带脆弱性及地质灾害评估与防治(2015-026)

摘　　要：海洋沉积物为环境和古气候再造提供良好的地质示踪记录,其中海洋黏土矿物被作为有效指标广泛应用。黏土矿物的预处理方法对其相对组成计算结果影响较大,因此寻找适合不同海域环境简便而有效的预处理方法是黏土矿物研究中很有意义的工作。从渤海中部和印度洋海盆选取2个表层沉积物样品分别代表浅海和深海沉积物,采用不同的预处理方法进行处理。通过其X射线衍射(XRD)测试结果进行对比分析,探索适合特定区域黏土矿物的预处理方法。结果显示,预处理中使用的双氧水、盐酸、醋酸和连二亚硫酸钠-重碳酸钠-柠檬酸钠(DCB)等都对样品黏土矿物分析结果产生一定的影响。若碳酸盐衍射峰不掩盖黏土矿物的信息表达,可不用盐酸或者醋酸去除碳酸盐;DCB方法去除氧化铁时所加试剂会与黏土矿物层间离子发生交换导致数据失真,因此建议一般不使用;去除有机质能促使黏土矿物更好的分散,且质量分数为10%的H_2O_2为最佳。Marine sediments record abundant information of paleoenvironment and paleoclimate,and marine clay minerals are widely used as indicators to study sediment source and dynamic conditions.Different region has various factors controlling the clay minerals,which contribute to multiple pretreatment methods.However,the pretreatment methods of clay minerals have a great influence on the analytical results.It’s important to search for the proper pretreatment method for particular areas.In this study,two surface sediment samples were collected from the Bohai Sea and the Indian Ocean,respectively.A variety of pretreatment methods were adopted,and the samples after pretreatment were analyzed by X ray diffraction（XRD）.The results show that pretreatment using hydrogen peroxide,acetic acid,hydrochloric acid,and sodium dithionite-citrate-sodium bicarbonate（DCB）,have a significant influence on clay mineral compositions of the samples.It is not necessary to remove the carbonate components unless its information overwhelm that of clay minerals.DCB method（removing iron oxide）can promote the dispersion of samples,which can favor extraction of clay minerals.Reagents in this method can exchange with ions in the interlayer of clay minerals,and results in data distortion.Therefore,it is not recommended to use DCB pretreatment methods.The removal of organic matter by hydrogen peroxide can lead to better dispersion of clay minerals,and the 10% H2O2 shows the best result.

关 键 词：黏土矿物 有机质 碳酸盐 氧化铁 X射线衍射 

分 类 号：P736.21[天文地球—海洋地质]