Chinese Science Bulletin

, Volume 50, Issue 20, pp 2369–2376

Stratigraphy and age of the Daohugou Bed in Ningcheng, Inner Mongolia

Authors

    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Zhonghe Zhou
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Huaiyu He
    • Institute of Geology and GeophysicsChinese Academy of Sciences
  • Fan Jin
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Yuanqing Wang
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Jiangyong Zhang
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Yuan Wang
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Xing Xu
    • Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences
  • Fucheng Zhang
    • Institute of Geology and GeophysicsChinese Academy of Sciences
Articles

DOI: 10.1007/BF03183749

Cite this article as:
Wang, X., Zhou, Z., He, H. et al. Chin.Sci.Bull. (2005) 50: 2369. doi:10.1007/BF03183749

Abstract

Recent fieldwork has extended the distribution of the Daohugou Bed deposits from the Daohugou Village to its several neighboring areas. The fossil-bearing Daohugou deposits uncomformably overlie complex bedrocks, and comprise three major parts. The red shales in the lower part were misidentified as belonging to the Tuchengzi Formation. Field excavation has indicated that the shales of upper part of the bed are the major fossil-bearing horizon. Due to strong tectonic activities, sediments were often folded with the sequences inverted in the region. Some newly recognized contacts between the Daohugou Bed and the volcanic rocks showed that the ignimbrite of the Tiaojishan Formation (159–164 Ma) underlies the Daohugou deposits, rather than overlying the latter as previously proposed. Thus, the age of the Daohugou deposits should be younger than the age of the ignimbrite, and thus it was incorrect to correlate the Daohugou Bed with the Middle Jurassic Jiulongshan Formation. Although biostratigraphic studies based on conchostracans and insects support a Middle Jurassic-early Late Jurassic age for the Daohugou deposits, vertebrate fossils such asLiaoxitriton, Jeholopterus and feathered maniraptorans show much resemblance to those of the Yixian Formation. In other words, despite the absence ofLycoptera, a typical fish of the Jehol Biota, the Daohugou vertebrate assemblage is closer to that of the Early Cretaceous Jehol Biota than to any other biota. We propose that the Daohugou fossil assemblage probably represents the earliest evolutionary stage of the Jehol Biota based on both vertebrate biostratigraphy and the sedimentological and volcanic features which suggest the Daohugou deposit belongs to the same cycle of volcanism and sedimentation as the Yixian Formation of the Jehol Group.

Keywords

Inner MongoliaDaohugou BedYixian Formationstratigraphic sequenceEarly CretaceousJehol Biota

Copyright information

© Science in China Press 2005