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本文通过交变退磁后的古地磁测定结果,着重讨论了张汴塬黄土古地磁特征及黄土地层划分。古地磁测定结果表明:早更新世与中更新世黄土界线和布容与松山之间界线吻合,在剖面的下粉砂层顶部。中更新世黄土始于73万年。在布容正极性世中,第二层古土壤中出现反极性标本,有可能是反极性事件。早更新世沉积物中显示出哈拉米洛与奥尔都维两个事件。最底部出现的正极性标本可能是留尼昂事件的反映,因此陕县黄土可能形成于240万年左右。在中国黄土中发现留尼昂事件的剖面还不多。为进一步搞清这几个事件,目前正在进一步工作。此外本文还研究了标本的虚磁极位置,以及强度与岩性的关系。
In this paper, the paleomagnetic characteristics of loess in Zhangbaoyuan area and the division of loess strata are mainly discussed by the paleomagnetic test results after alternating demagnetization. Paleomagnetism measurements show that the boundaries between the Early Pleistocene and Middle Pleistocene loess boundaries and cloths and Matsuyama coincide with the top of the lower silt layer in the section. The Middle Pleistocene loess began in 730,000 years. In the positive polar world of cloth, there are reverse polarity samples in the second layer of ancient soil, which may be reverse polarity events. Early Pleistocene sediments show two events of Haramillo and Ordu. The most positive positive specimen may be a reflection of the Reunion event, so Shanxian loess may form about 2.4 million years. There are not many profiles of Reunion found in Chinese loess. To further clarify these events, further work is currently under way. In addition, this paper also studied the specimen’s virtual magnetic pole position, as well as the relationship between strength and lithology.