关键词: 古环境；磁化率；粒度；七顶山

Abstract:

The results of the magnetic susceptibility of the Qidingshan loess varies in a range of 5.21×10^-8m³ kg^-1 to 42.42×10^-8m³ kg^-1, which is much lower than in other localities. The vertical changes of magnetic susceptibility and grain have a positive relation. The magnetic minerals are mainly focused on over 8ф in grain size. A comparison in Oxide isotope indicates that Qds20—Qds28 is consistent with the 3rd section of Guliya ice core and with abyssal 3a, 3b and 3c sub-section in fluctuation, and that Qds28—Qds31 is analogous with the 2nd section of Guliya ice core and with abyssal 2nd section. The study reveals during 60 to 22 ka BP the Malan loess sedimentation period is generally dry and cold with an interim warm and wet climate.

Key words:

paleoenvironment; magnetic susceptibility; grain size; Qidingshan