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Chinese Science Bulletin

, Volume 46, Issue 17, pp 1473–1476 | Cite as

Magnetic polarity ages of the fossil-bearing strata at the Si-hetun section, West Liaoning: A preliminary result

  • Yongxin Pan
  • Rixiang Zhu
  • Shaw John
  • Yaoxiu Zhou
Notes

Abstract

Rock-magnetic and palaeomagnetic studies have been carried out on the interval of famous fossil-bearing sedimentary rocks and its overlying basalts and underlying basalts at the Sihetun section, West Liaoning Province. Normal polarity was obtained for the sedimentary interval and the underlying basalts, while reversed polarity was found in the overlying basalts. Taking account of the new40Ar/39Ar ages (Swisher et al., 1999), we classified the fossil-bearing sedimentary interval into the Barremian M3n zone (Early Cretaceous age). Several abnormal horizons on magnetic properties, probably corresponding to the tuffs, were observed in the fossil-bearing sedimentary interval. This implies that the massive bio-extinction may link to dramatic environmental changes that were caused by volcanic eruptions.

Keywords

magnetic polarity age Jehol fauna Sihetun section 

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Copyright information

© Science in China Press 2001

Authors and Affiliations

  • Yongxin Pan
    • 1
  • Rixiang Zhu
    • 1
  • Shaw John
    • 2
  • Yaoxiu Zhou
    • 3
  1. 1.Institute of Geology and GeophysicsChinese Academy of SciencesBeijingChina
  2. 2.Geomagnetism LaboratoryUniversity of LiverpoolLiverpoolUK
  3. 3.The Aviatic Remote Sensing CenterMinistry of Land and ResourcesBeijingChina

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