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对山西宁武公海GH09B1孔2.8m长岩芯进行的磁化率、非磁滞剩磁、等温(饱和)剩磁、J-T曲线、磁滞回线和XRD等测试结果表明,GH09B1孔岩芯磁性矿物以磁铁矿为主,磁性矿物含量高的岩芯段,磁性颗粒也较细,形成于湖盆流域土壤发育较强、降水量较多的时期,而磁性矿物含量低的时期则相反.公海湖泊沉积物环境磁学参数变化主要受控于湖盆流域土壤发育程度,进而指示亚洲夏季风强弱,尤其是χ与S-300参数清晰地记录了近1200年来宁武公海地区夏季风的变化历史,发现中世纪暖期(910～1220AD)显著湿润,夏季风强盛,这一结果得到同岩芯孢粉记录的支持.3～6年分辨率的环境磁学参数记录还显示,中世纪暖期内部存在980～1050AD的次级干旱阶段.公海沉积物磁学参数记录的近千年夏季风变化与历史文献记载、万象洞石笋氧同位素和气候模拟结果一致,共同指示了中世纪暖期季风强盛的湿润气候环境且内部存在百年尺度的气候干湿波动.环境磁学参数可作为高分辨率湖泊沉积记录的季风气候变化的有效参数.
Magnetic susceptibility, non-hysteresis remanence, isothermal (saturation) remanence, JT curve, hysteresis loop and XRD were measured on GH09B1 2.8m long core in the Ningwugaohai of Shanxi Province. The results show that the magnetic core of GH09B1 The magnetite-based core fraction with high magnetic mineral content also has fine magnetic particles, which formed during the period when the soil in the lake basin developed strongly and had a large amount of precipitation, while the period with low content of magnetic minerals was opposite. The change of magnetic parameters of lake sediment environment is mainly controlled by the degree of soil development in the lake basin, which in turn indicates the strength of the Asian summer monsoon. In particular, χ and S-300 parameters clearly record the changes of the summer monsoon in the Ningwu high seas over the past 1200 years History and found that the warm period of Middle Ages (910 ~ 1220AD) was markedly humid and the summer monsoon was strong, and the result was supported by the same record of core sporopollen. The records of environmental magnetic parameters from 3 to 6 years of resolution also showed that the records of environmental magnetic parameters There is a secondary drought stage of 980 to 1050 AD.The changes of the nearly 1000-year summer monsoon recorded by the magnetic parameters of the high-sea sediments are consistent with the historical records and the stalagmite oxygen isotopes and climate simulation results of the Vientiane Cave, Climatic fluctuations present century scale and humid climate inside. Valid Parameter environmental magnetic parameters can be varied as a high-resolution recording Lacustrine monsoon climate.