欢迎访问《古脊椎动物学报》官方网站,今天是 分享到:

古脊椎动物学报 ›› 2022, Vol. 60 ›› Issue (1): 42-53.DOI: 10.19615/j.cnki.2096-9899.210716

• • 上一篇    下一篇

内蒙古阿拉善左旗乌兰塔塔尔最晚始新世-渐新世剖面的区域年代地层意义

Joonas Wasiljeff1(), 张兆群2,3,4()   

  1. 1 芬兰赫尔辛基大学地球科学与地理学系 赫尔辛基 00014
    2 中国科学院古脊椎动物与古人类研究所,中国科学院脊椎动物演化与人类起源重点实验室 北京 100044
    3 中国科学院生物演化与环境卓越创新中心 北京 100044
    4 中国科学院大学地球与行星科学学院 北京 100049
  • 收稿日期:2020-12-22 出版日期:2022-01-20 发布日期:2022-02-14
  • 基金资助:
    芬兰科学院基金(编号)(316799);中国科学院战略性先导科技专项(编号)(XDB26000000);中国科学院古生物化石发掘与修理专项、国家自然科学基金(批准号)(41472003);GeoDoc和Waldemar von Frenckell基金资助

Stratigraphical significance of Ulantatal sequence

Joonas Wasiljeff1(), ZHANG Zhao-Qun2,3,4()   

  1. 1 Department of Geosciences and Geography, University of Helsinki P.O. Box 64, Helsinki 00014, Finland
    2 Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences Beijing 100044, China
    3 CAS Center for Excellence in Life and Paleoenvironment Beijing 100044, China
    4 College of Earth and Planetary Sciences, University of Chinese Academy of Sciences Beijing 100049, China
  • Received:2020-12-22 Published:2022-01-20 Online:2022-02-14

摘要:

精确的区域年代地层框架是探究地质历史时期气候变化与动物群演化事件的基础。过去5000万年中亚洲地区发生的最明显陆地哺乳动物群转换事件可能发生在始新世-渐新世转折时期(约34 Ma)。然而由于缺乏连续的地层记录或者对经典哺乳动物化石地点的地层划分与对比存在较大争议,这一重要转折时期动物群的演变尚不明晰。内蒙古阿拉善左旗乌兰塔塔尔地区丰富的最晚始新世-渐新世(白音期、乌兰塔塔尔期与塔本布鲁克期)哺乳动物化石及连续的地层记录为建立该时段区域年代地层框架奠定了基础。基于岩石地层学、生物地层学以及磁性地层学研究结果,推荐将乌兰塔塔尔剖面作为渐新统乌兰塔塔尔阶的区域单位层型剖面。乌兰塔塔尔阶底界位于克克阿木剖面15.9 m处(33.89 Ma); 塔本布鲁克阶底界位于综合剖面98 m处(27.7 Ma), 对应古地磁极性年表的C9r, 以中华鼠兔Sinolagomys的最低出现为标志。

关键词: 内蒙古, 始新统, 渐新统, 层型剖面, 地层对比, 年代地层学, 生物地层学, 磁性地层学

Abstract:

Robust regional chronostratigraphic framework is the basis of understanding climatic and faunal events in the geologic history. One of the most dramatic faunal turnovers of the past 50 million years in Asia is linked to the Eocene-Oligocene Transition (EOT) at about 34 Ma. However, the chronostratigraphic relationships between faunal modulation and geologic events associated with the EOT in China have remained uncertain before and after the epoch boundaries, mainly due to the scarcity of continuous records and problems in correlating and subdividing the classic areas containing abundant mammalian fossils. Past decades have seen developments in establishing Chinese regional Paleogene Land Mammal Ages, and albeit many ages are well constrained, some, such as those of the latest Eocene and the Oligocene, have remained unsettled. In this paper, we present how recent evidence from the fossiliferous Ulantatal sequence, Nei Mongol, China, provides better constraints to the latest Eocene and Oligocene Chinese Land Mammal ages (Baiyinian, Ulantatalian, and Tabenbulukian). We propose Ulantatal sequence as a new regional unit stratotype section of the Ulantatalian stage, and the lower boundary of Tabenbulukian stage to be reassigned to Chron C9r (27.7 Ma), with the lowest occurrence of Sinolagomys as the marker horizon.

Key words: Nei Mongol, Eocene, Oligocene, stratotype section, stratigraphical correlation, chronostratigraphy, biostratigraphy, magnetostratigraphy

中图分类号: