摘要
文划分了大荔人化石层位上部的黄土 古土壤序列 ,对黄土进行了磁化率测量 ,并将结果与附近位于黄土塬上的垣雷剖面以及典型黄土洛川剖面的地层和磁化率曲线对比 ,认为大荔人化石地点地层上部黄土 古土壤序列包括S0 、L1、S1、L2 、S2 。大荔人化石位于黄土层以下约 2 0m处的河流相砾石层中 ,因此大荔人化石的年代大于S2 的轨道调谐年龄 ,即 0 2 4 7MaB .P .。根据动物化石和孢粉指示的环境以及化石层位上堆积较厚的河流相地层 。
Since Dali man Site discovered in 1978, much research has been done for the strata, the palaeolithic, the mammalian fossils etc., however no agreement has been made on the age of the fossil Dali man. The main reason lies in not only there being no consolidate dating method, but also in how researchers dealing with the lithostratigraphy of the loess paleosol successions overlying fluvial deposits bearing Dali man fossil. In this paper,the stratigraphic section is analyzed, the magnetic susceptibility of the loess paleosol measured. Our results show the strata of Dali man section consisting of two kinds of sediments from the top to the bottom: the loess paleosol succession and fluvial deposits. The former, in thickness about 17m, includes S 0, L 1, S 1, L 2 and S 2, so the age of the Dali man should be older than 0 247 Ma B.P. according to the Orbit Tuning Mode which gives S 2 an age of 0 247 Ma. Since the sporopollen and mammilla fossil suggested a more humid period than that of today, it could be inferred that Dali man lived in an interstadial period. Together with the fact that the horizon bearing the fossil Dali man is more than 20 m below the loesspaleosol succession, an age span of 028～033 Ma B.P. when S 3 developed is suggested for the Dali man fossil.
出处
《地质科学》
CAS
CSCD
北大核心
2001年第3期364-369,共6页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家自然科学基金重大项目"中国季风区古环境演变机制及其全球变化的动力学联系"(编号 :4 9891 70 )资助
