• 责任者：Zhang Ju (State Key Laboratory of Palaeobiology and Stratigraphy ; Nanjing Institute of Geology and Palaeontology ; Chinese Academy of Sciences ; Nanjing 210008 ; China) ; Zhang Yuandong
• 刊名：Journal of Stratigraphy
• 出版年：2013
• 卷期：37(1)
• 关键词：奥陶纪 ; Ordovician ; 生物地层学 ; biostratigraphy ; 笔石纲 ; Graptolithina ; 云南 ; Yunnan Province
• 页码：p.8-17
• 图表：illus., 39 refs.
• 分类号：1200
• issnNo：ISSN0253-4959
• isbnNo：CN32-1187/P

The Hungshihyen Formation is characterized by its reddish, coarse clastics deposits, and is distributed in eastern Yunnan and southwestern Sichuan. The formation contains graptolites, chitinozoans and acritarches and other fossils, based on which the formation has traditionally been regarded as of Arenig （Floian and Dapingian） age. Recently, we recollected many graptolites from three sections of the formation in eastern Yunnan, including the Guihuaqing Reservoir bank section and the Liujiang section in Luquan county, and the Hongshiya section near Ercun, Kunming. Some 600 specimens have been obtained, which are identified to belong to 2 genera and 15 species. Based on this graptolite fauna, the Coryrnbograptus varicosus Zone is identified for the graptolite-bearing interval in the middle part of the formation. The biozone is well correlated with the equivalent Corymbograptus varicosus Zone of Lake District in Britain, the ＂Baltograptus deflexus Zone＂ in the Acoite Formation of northwestern Argentina, and the Acrograptus filiforrnis Zone in the northern Guizhou area of Upper Yangtze Region, and is thus of early-middle Floian age, rather than late Floian age as previously regarded. This suggests that the entire Hungshihyen Formation may span only the Floian Stage, representing a relatively short time interval. As the Hungshihyen Formation is overlain by the Qiaojia Formation, which is of Darriwilian age, it seems likely that Dapingian strata are largely absent in the region.