The rudimentary form of ancient continent of China has been formed in the Jurassic. The Jurassic stratigraphy in China is dominated by continental sediments. The stratigraphic division, biostratigraphic correlations, and isotope chronology have been inconsistent. Recently, a paper titled 'Jurassic integrative stratigraphy and timescale of China' has been published in Science China - Earth Sciences by Prof. Diying Huang from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, which provides a synthetic overview of these issues.
The Yanshan Movement has had a profound influence on the eastern and northern regions of China and has formed important regional unconformities. The early Early Jurassic sediments generally were lacking in the eastern and central regions north of the ancient Dabie Mountains, suggesting that a clear uplift occurred in the eastern part of China during the Late Triassic period when it formed vast mountains and plateaus. The geological age and markers of the boundary between the Yongfeng Stage and Liuhuanggou Stage are unclear, although the boundary may lies in the middle Early Jurassic. The onset of the Middle Jurassic Yanshan Movement was represented by a set of syngenetic conglomerate at the bottom of the Haifanggou or Longmen Fms. in the Yanliao region, which is equivalent to the bottom of the Shihezi stage (ca. 168 Ma). The bottom of the Manas Stage creates a regional unconformity in northern China (about 161 Ma). This study indicated that the Jurassic Yanshan Movement is likely related to the southward subduction of the Siberian Plate and the closure of the Mongolia-Okhotsk Ocean. The Fifth Stage of the Jurassic terrestrial stage in China is marked by a warming event at the top of the Toutunhe Formation, and the change in the biological assemblages is estimated to be 155 Ma. The terrestrial Jurassic-Cretaceous boundary in the Yanliao region should be located in the upper part of the Tuchengzi Formation, the Ordos Basin in the upper part of the Anding Formation, the Junggar Basin in the upper part of the Qigu Formation, and the Sichuan Basin in the upper part of the Suining Formation. With the origin and development of the Coniopteris-Phoenicopsis flora, the Yanliao biota was developed and reached its great prosperity in the Early Late Jurassic and gradually declined and disappeared and moved southward with the arrival of a dry and hot climate.
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See the article: Huang, D. Sci. China Earth Sci. (2018). https://doi.org/10.1007/s11430-017-9268-7
Journal
Science China Earth Sciences