中国南方红土磁化率的古气候意义研究

Study on the paleoclimate implications of magnetic susceptibility of the red soils in southern China

黄土-古土壤的磁化率作为反演古气候演化的物理参数在中国、中亚、欧洲和北美等地均得到了证实,被广泛用于海陆气候对比和定量重建古气候。自此之后,不同学者尝试将磁化率反演古环境的应用范围从黄土-古土壤扩大到中国南方红土。然而对磁化率这一物理参数能否作为反演古气候的代用指标完全适用于中国南方红土依然存在很大分歧,甚至是截然相反的认识。显然要准确理解红土磁化率是否具有明确的古气候意义,就需要研究黄土-古土壤磁化率之所以能作为古气候代用指标的物理化学机制,以及红土沉积物是否和黄土-古土壤一样具有相似的磁性矿物形成机理。因此本文在总结黄土-古土壤磁学性质(磁性矿物的形成机理、磁性矿物的种类及粒度特征)的基础上,来讨论红土磁化率参数是否具有明确的古气候意义。

As an important successful tool to deduce the paleoclimate,magnetic susceptibility is widely used in China,Central Asia,European and North America.Since then,many scholars have tried to use magnetic susceptibility to deduce the paleoclimate of red soils in southern China.However,if magnetic susceptibility could be used as a successful tool to deduce the paleoclimate of red soils in southern China,it is also a question.About this view,there is also some disputes.Obviously,if magnetic susceptibility can be used as a tool to deduce the paleoclimate of red soils in southern China,there must be to study the reason why magnetic susceptibility can be used to deduce the paleoclimate in loess and to study if there are the same mechanism of magnetic mineral between loess and red soils in southern China.So,we firstly sum magnetic property of the loess and then discuss if magnetic susceptibility of red soils in southern China can be as a successful tool to deduce the paleoclimate.