深海铁锰结壳磁性地层学和岩石磁学研究

深海铁锰结壳不仅是有潜在经济价值的海底矿产，而且是示踪百万-千万年尺度古海洋环境变化的天然样本，被视为古海洋学和全球变化研究的理想示踪剂。铁锰结壳的定年研究则是重建古海洋环境的前提。研究表明铁锰结壳生长过程中记录古地磁极倒转，因此可以通过高分辨率磁性地层学确定其形成年龄。然而，铁锰结壳岩石磁学和环境磁学缺乏系统深入研究。据此，申请人拟通过对2018年4月“嘉庚号”南海无人遥控深潜航次所采集的铁锰结壳、铁锰结壳表面沉积物和海山底部海底沉积物短柱样品，开展详细的磁性地层学、岩石磁学和环境磁学研究，明确铁锰结壳磁性矿物种类、磁学属性和来源，揭示铁锰结壳环境磁学记录的古海洋古气候信息，探讨边缘海和开放大洋铁锰结壳生长速率和成因机制上的差异。

Deep-ocean ferromanganese crusts are not only potentially economically valuable seabed minerals, but also natural samples for tracing paleo-oceanic environmental changes at the scale of millions to tens of millions of years. They are regarded as ideal tracers for paleo-oceanography and global change research. The chronological study of ferromanganese crusts is the precondition for reconstructing the paleo-marine environment. Researches showed that records of natural remanent magnetization and geomagnetic polarity reversals were preserved in ferromanganese crust and the application of fine-scale magnetostratigraphic analysis has been successfully demonstrated. However, there is a lack of systematic and in-depth study on rock magnetism and environmental magnetism of ferromanganese crusts. Here, the applicant intends to carry out detailed magnetostratigraphy, rock magnetism and environmental magnetism studies on ferromanganese crusts, surface sediments of ferromanganese crusts and short columns of deep-sea sediments collected from the South China Sea during "Jiageng" Remote Operated Vehicle (ROV) Exploration in April 2018, to clarify the types, magnetic properties and sources of magnetic minerals in ferromanganese crusts. The purpose is to reveal the paleoclimate information recorded by environmental magnetism of ferromanganese crusts and to explore the differences in growth rate and genetic mechanism of ferromanganese crusts between marginal sea and open ocean.