Popis: |
The present paper deals with the composition, features and the geological age of the flora from the Zhenzhuchong Formation, northeast of Sichuan Province. The plant fossils recovered include 95 species of 57 genera. This flora may be classified as: Ptilophyllum-Coniopteris assemblage of the Dictyophyllum-Clathropteris Series equivalent to the Pliensbachian-Aselian Stage. In this sense, the flora may be compared with that of the Thaumatopteris zone in Greenland and Sweden. The Jurassic palaeoclimate in the Sichuan Basin is studied on the evidence of sedimentary environment and coal-formation. It is concluded that an increase in humidity and decrease in temperature were favourable to the formation of coal. |