新近系谢家阶层型剖面古地磁年代学研究  

MAGNETOSTRATIGRAPHY OF STRATOTYPE SECTION OF THE NEOGENE XIEJIAN STAGE

作　　者：武力超[1] 岳乐平[1] 王建其[1] F.Heller 邓涛[3] 

机构地区：[1]西北大学大陆动力学教育部重点实验室,西北大学地质系陕西西安710069 [2]Institute of Geophysics,ETH,Zurich,Switzerland [3]中国科学院古脊椎动物与古人类研究所,北京100044

出　　处：《地层学杂志》2006年第1期50-53,共4页Journal of Stratigraphy

基　　金：国家自然科学基金项目(No.40372202);国家973项目(2003CB214607);全国地层委员会"中国主要断代地层建阶研究"项目

摘　　要：古地磁测量表明,中国新近系谢家阶界线层型剖面——西宁盆地谢家剖面共记录了18个正极性段与17个负极性段,与标准极性柱中C5Bn.2n—C7n.1n之间的极性带能很好的对应。剖面中谢家组的年龄为17.32—21.58Ma,谢家哺乳动物群的年龄约为21Ma,相当于MN2中期。Paleomagnetic measurements of the Xiejia section demonstrate that the stratotype of the Neogene Xiejian Stage in China records 18 normal and 17 reversed polarity zones. These polarity zones corresponded very well to the polarity zones between C5Bn. 2n and C7n. In in the time scale of Lourens et al. （2004）. We use internterposition method to calculate the age. The geological age of the Xiejia Formation is 17.32-21.58 Ma. It was dated between the late and middle time of Early Miocene. So, the upper sediments of the Xiejia Formation deposited in late Early Miocene. The upper sediments of the Mahalagou Formation deposited in Early Miocene. The paleomagnetic age of the Xiejia Mammal Fauna is about 21 Ma, corresponding to MN2.

关 键 词：新近系 谢家阶 年代地层学 古地磁 西宁盆地 青海 

分 类 号：P534.61[天文地球—古生物学与地层学] P539[天文地球—地质学]