云南高原红壤南北磁性特征分析  

Study on magnetic characteristics of red soil in Yunnan Plateau

作　　者：李峰锐 李海侠[1] 刘大祥 任二慧 李刚强 陈宇东 张子豪 Li Fengrui;Li Haixia;Liu Daxiang;Ren Erhui;Li Gangqiang;Chen Yudong;Zhang Zihao(School of Land and Resources Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093

出　　处：《化工矿物与加工》2021年第8期20-25,共6页Industrial Minerals & Processing

基　　金：国家自然科学基金项目(41664003)。

摘　　要：云南高原红壤具有纬度地带性与垂直梯度带明显的优势,是研究降雨、温度等气候条件及海拔高度变化引起的水热条件改变对土壤磁性影响的理想场所,了解不同地区土壤磁性变化有助于正确解释和应用磁参数。对比分析了云南高原红壤南北典型气候区土壤剖面磁化率的分布特征、磁性矿物类型和磁畴状态的变化,结果表明:云南高原红壤南北样地土壤低频质量磁化率和百分比频率磁化率在垂直剖面的趋势基本一致,磁性总体表现为北方样地土壤磁性明显低于南方样地红壤磁性;北方样地土壤磁性颗粒主要以超顺磁(SP)为主,南方样地土壤表现为表层主要以SP颗粒为主,底部主要表现为SP、SD(单畴)和MD(多畴)颗粒共存,且风化成土作用较强。热磁曲线表明南北样地表层土壤均以亚铁磁性矿物为主,如磁铁矿和磁赤铁矿;并且随着土壤深度的增加,反铁磁性矿物的含量相应增大,如赤铁矿和针铁矿。The red soil in Yunnan Plateau differs obviously from latitudinal zones and vertical gradient zones.It is an ideal place to study the influence of weather conditions such as rainfall and temperature and the change of water and heat conditions with the altitude on soil magnetism and to understand the soil magnetism varied in different regions,which is helpful to correctly explain and apply magnetic parameters.The distribution characteristics and the change of magnetic minerals and magnetic domain were studied by comparing the magnetic susceptibility of red soil profiles in south and north regions under typical weather conditions in Yunnan Plateau.The results show that the trend of low frequency mass susceptibility and percentage frequency susceptibility in the vertical profile is basically identical and the overall magnetic performance of the northern red soil sample is evidently lower than southern region.The magnetic particles of the northern red soil are predominately super-paramagnetic(SP),while the surface soil in south is also mainly SP,but the bottom is composed of the particles with co-occurrence of SP,SD and MD and strong weathering process.The thermomagnetic curves show that the surface soils in the north and south regions are mainly composed of ferromagnetic minerals such as magnetite and magnetic hematite.With the increase of soil depth,the content of antiferromagnetic minerals such as hematite and goethite in the soil increases.

关 键 词：高原红壤 磁化率 磁参数 磁性特征 热磁曲线 磁赤铁矿 磁化强度 

分 类 号：P53[天文地球—古生物学与地层学] S153[天文地球—地质学]