乐志军;陈家胜;刘秀铭;谢振龙;彭超;李培意;

• 1:福建师范大学地理科学学院
• 2:福建师范大学湿润亚热带山地生态国家重点实验室培育基地
• 3:福建师范大学地理研究所
• 4:麦考瑞大学环境与地理系

摘要(Abstract)：

探索古土壤层磁化率低值的原因,选取Kurtak剖面的20个典型黄土-古土壤样品测量等温剩磁(IRM)获得曲线.基于样品的IRM获得曲线符合累积对数高斯模型,所有样品拟合出3个矫顽力组分.组分1 (<30 m T)是成壤组分,组分2 (60～100 m T)是碎屑组分,组分3 (>100 m T)是赤铁矿或针铁矿;组分2是Kurtak黄土的主要磁性矿物,其含量变化受控于风速变化. CBD处理后所有样品只拟合出组分2,且CBD处理前后样品的磁化率值呈正相关性,指示碎屑组分是影响剖面磁化率的主要因素.黄土-古土壤层中都存在针铁矿,但针铁矿的含量不足以影响整个剖面磁化率的变化;而Kurtak黄土中的赤铁矿与针铁矿也可能是在源区生成,表明组分3也能指示源区信号.

关键词(KeyWords)： 西伯利亚黄土;IRM;矫顽力组分;磁化率;碎屑组分;CBD方法

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金资助项目(U1405231、41772180、41602190)

作者(Authors): 乐志军;陈家胜;刘秀铭;谢振龙;彭超;李培意;

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