A new mechanism for the magnetic enhancement of hematite during heating:the role of clay minerals
作者单位：State Key Laboratory of Lithospheric EvolutionInstitute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Cenozoic Geology and EnvironmentInstitute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution
会议名称：《中国科学院地质与地球物理研究所2012年度（第12届）学术年会》
会议日期：2013年
学科分类：0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学]
基 金：financially supported by the National Nature Science Foundation of China(Grants 40804014,40821091) the Chinese Academy of Sciences(CAS) GAP is supported by a Young Intcrnational Scicntist Fcllowship from thc CAS QSL furthcr thanks thc support from thc ’100 Talent Program’ of the CAS
关 键 词：clay minerals saponite montmorillonite kaolinite chlorite magnetic enhancement hematite thermomagnetic analysis
摘 要：The magnetic properties of loess,lake,and ocean sediments are often used as indicators for paleoclimatic/paleoenvironmental *** analysis is a conventional approach for identifying magnetic phases and thermal alteration of *** concentration parameters are often enhanced after thermal treatment. In this study,the role of clay minerals in magnetic enhancement at elevated temperatures is systematically *** results indicate that the clay minerals(saponite, Ca-montmorillonite,kaolinite,and chlorite) are dominated by paramagnetic behaviour and that the magnetic properties remain relatively stable after heating to 700℃in argon. In contrast,mixtures of hematite and chlorite,have a high degree of magnetic enhancement after heating in argon,which indicates that clay minerals play important role in magnetic *** results improve our understanding of the processes involved in complicated mineral transformations,which is important for retrieving paleoclimatic/paleoenvironemntal signals from magnetic proxies.