In the greater inland Jianghan Basin of South China,three salt depressions are lacking accurate geological times,of which Jiangling Depression is the largest.Evaporites are important records of paleoclimate,however,the geological ages of evaporates are very difficult to be determined because often evaporates have scare macrofossils and microfossils.Nonmarine Cretaceous to Tertiary halite deposits interbedded with mudstones are widely distributed in China.Paleocene-Eocene Thermal Maximum had very high temperatures and attracted strong interests of geologists because these times can be compared with future climate change because of global warming.However,previous studies focused on marine sediments found that during the Paleocene-Early Eocene,massive evaporate deposits formed in Jiangling depression of the Jianghan Basin.In this paper,the authors show that the Shashi Formation halite deposits formed in the Paleocene according to palynology.Most of these palynology fossils are arid types,so the massive evaporites in the Jiangling depression could be closely related to the hot Paleocene climate.High temperatures during the Paleocene contributed to the formation of the massive evaporates in the Jiangling Depression,until sylvite was the result.
Chun-lian WangCheng-lin LiuJiu-yi WangXiao-can YuKai Yan
As a more efficient quantitative method for morphological analysis, geometric morphometrics is applied to the flabellate fossils Flabellophyton including Flabellophyton lantianensis and Flabellophyton strigata from Neoproterozoic Ediacaran Lantian biota, South China. Both traditional morphometric analysis （including diverging angle, length, and width distribution） and geometric morphometric analysis [including superposition of normalized area analysis, non-metric multidimensional scaling （n-MDS）, Bray-Curtis similarity cluster analysis （CLUSTER） and analysis of similarities （ANOSIM）[ were performed. The results indicate there are great interspecific morphological differences between F. lantianensis and F. strigata, in addition to some intraspecific variations within each species. Here we preliminarily suggest that the previously defined Flabellophyton should be subdivided into 2 genera at least： one marked by the dark transverse striated structure, and the other without. This recharacterization and reclassification work still needs further careful observation and comprehensive analysis with large number of flabeilate fossils combining morphology, structure, population, and community-ecology study.
WAN BinYUAN XunlaiCHEN ZheGUAN ChengguoPANG KeTANG QingRAO Xin
