风尘沉积的磁学参数与环境意义  

The magnetic parameter and environmental significance of eolian deposit

作　　者：滕飞[1] 叶玮[1] 朱丽东[1] 

机构地区：[1]浙江师范大学地理与环境科学学院,金华321004

出　　处：《干旱区资源与环境》2012年第5期52-58,共7页Journal of Arid Land Resources and Environment

基　　金：国家自然科学基金项目(41071002)资助

摘　　要：以磁化率、频率磁化率为代表的一系列磁学参数被广泛用于环境变化研究中。然而,关于磁学参数的环境意义尚存在较多的争论。结合前人研究成果,对中国南北方风尘沉积磁学参数应用成果进行了对比分析。结果表明:不同类型风尘沉积的磁化率含义存在差异,并且具有一定的地带性。黄土与古土壤磁化率高低差异具有地域性,不同纬度、不同气候、不同环境条件下黄土、古土壤磁化率所记录的环境信息含义差别较大,存在风速变化、成壤强弱和物源差异等多种形成机制;新近纪红粘土与黄土具有不同的形成环境,但其磁参数可以反映成壤作用的强弱,进而指示新近纪夏季风的变迁;以下蜀土和加积红土为代表的中国南方的风尘沉积磁学参数的变化与气候变化相关联,磁化率记录了成壤环境的差异,特别是土壤水分的不同。因此,在亚热带地区,用磁化率作为记录古气候冷暖变化的代用指标不能简单照搬其他区域的模式。Magnetic susceptibility and frequency dependent magnetic susceptibility as a representative of the magnetic parameter are widely applied in the research of environmental change. However, there exist some dif- ferent opinions about the environmental significance of magnetic parameter. We analyzed and contrasted the a- chievement about magnetic parameter of eolian deposit in southern and northern China. Results indicate that magnetic susceptibility in different types of eolian deposit are dissimilar and zonal. Differences of magnetic sus- ceptibility in loess and paleosoil are regional. Neogene red clay and loess have different formation environment, but its magnetic parameter can still reflect the pedogenic degree and then indicate the changes of summer mon- soon. In southern China, the magnetic parameters of eolian deposit which represented by Xiashu loess and aggra- dational red earth are relats to the climate change. Magnetic susceptibility recorded the differences of pedogenic environment, especially the differences of soll moisture. Therefore, great care should be taken when using mag- netic susceptibility as a indicator for study of Dalaeoclimatic change

关 键 词：磁化率 环境磁学 风尘沉积 环境变化 

分 类 号：P532[天文地球—古生物学与地层学]