| 中国三叠纪孢粉组合特征及其分区的初步探讨 |
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| A PRELIMINARY DISCUSSION ON THE CHARACTERISTICS AND STRATIGRAPHIC DIVISIONS OF TRIASSIC SPORES AND POLLEN IN CHINA |
| Being well-developed and widespread, the Triassic in China occursin two sedimentary domains, the north and south domains separated bythe Qinling-Kunlun and characterized by fossil spores and pollen.The north sedimentary domain, represented by the Shaanxi-Gansu-Ningxia Basin and Qingshui Basin, is characterized by continental Triassic, with three spore and pollen assemblage zones enumerated in ascending order as follows. 1. The Lundbladispora-Taeniaesporites assemblage zone is eiquvalent in horizon to Early Triassic Liujiagou Formation (T_11) and Heshanggou Formation (T_12). It may be subdivided into two subzones, that is,the lower Lundbladispora-Taeniaesporites-Cycadopites subzone and the upper Lundbladispora-Verrucosisporites-Taeniaesperites subzone. 2. The Punctatisporites-Chordasporites assemblage zone corresponds toErnma Formation (T_12) and Tongchuan Formation (T_22), of MiddleTriassic age. This assemblage is composed of two assemblage subzones,the lower Punctatisporites-Chordasporites-Plicatipollenites subzone and theupper Punctatisporites-Granulatisporites gigantus-Chordasporites subzone. 3. The Dictyophyllidites-Apiculatis poris-Lueckisporites triassicus assemblage zone equals in horizon to the Yanchang Formation, of LateTriassic. Abundant megaspores have been also found in all those assemblagezones of Triassic. The south sedimentary domain: The Middle and Lower Triassic consists mainly of marine deposits, yielding spores and pollen in a few localities, while the upper Triassic is made up of continental or paralicdeposits rich in sporopollen assemblages. As represented by their development in Sichuan and Guizhou, the middle and upper series are subdivided into three assemblage zones: 1. The Verrucosisporites-Corisaccites assemblage zone corresponds inhorizon to the Middle Triassic Guan1in Formation in Weining, Guizhou. 2. The Corollisporites-Micrhystridium assemblage zone is equivalentin horizon to the early Late Triassic Maantang Formation in Sichuan. 3. The Kyrtomisporis-Ricciisporites assemblage zone equals inhorizon to Xujiahe Formaton in Sichuan, of middle and late phases ofLate Triassic. Equivalent beds bearing this assemblage are also rich inmegaspores which are composed of Trileites pinguis, Bacutriletes tylotus,Nathorstisporites hopliticus etc. The data indicated that sporopollen assemblages of the south sedimentary domain are quite different from those of the north domain andthat such a sporopollen difference is consistent with the conclusion reached for the existence of Triassic floral provinces. |
| QU Li-fan,YANG Ji-rui,BAI Yun-hong,ZHANG Zhen-lai.1983.A PRELIMINARY DISCUSSION ON THE CHARACTERISTICS AND STRATIGRAPHIC DIVISIONS OF TRIASSIC SPORES AND POLLEN IN CHINA[J].Acta Geoscientica Sinica,5(1):81-94. |
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