The Givetian-Frasnian boundary at Liujing, Guangxi, South China is for the first time recognized and correlated in high resolution using characteristic chemocycles of element abundance fluctuation integrated with cono...The Givetian-Frasnian boundary at Liujing, Guangxi, South China is for the first time recognized and correlated in high resolution using characteristic chemocycles of element abundance fluctuation integrated with conodont biostratigraphy. The first appearance of Ancyrodella rotundiloba early form is as a biomarker, and the boundary of lowering fluctuation of element abundance followed by a sequence of characteristic chemocycles with a sequence of conodonts is as an abiotic auxiliary marker. The error is not more than 0.10 Ma. The study indicates that in a quiet interval, characteristic chemocycles integrated with biomarkers can be used for boundary recognition and regional correlation in high resolution, and this method has potential for intercontinental展开更多
The Caiziyan Middle and Upper Devonian boundary section is located approximately 30 km northeast of Guilin. It hosts relatively abundant benthic and common-rare pelagic fossils, including brachiopods, corals, tentacul...The Caiziyan Middle and Upper Devonian boundary section is located approximately 30 km northeast of Guilin. It hosts relatively abundant benthic and common-rare pelagic fossils, including brachiopods, corals, tentaculites, and conodonts, which may serve as a better suitable section for pelagic and neritic stratigraphic correlation. In this section, 10 ＂standard＂ conodont zones are recognized across the Givetian-Frasnian boundary, including, in descending order, the Lower hassi Zone, punctata Zone, transitans Zone, the Upperfalsiovalis Zone, the Lowerfalsiovalis Zone, disparilis Zone, the Upper hermanni-cristatus Zone, the Lower hermanni-cristatus Zone, the Upper varcus Zone, and the Middle varcus Zone, all of which are defined by the first occurrence of their defining conodont species. The Middle-Upper Devonian （Givetian-Frasnian） boundary is defined by the first occurrence of Ancyrodella pristina in accordance with the Global Stratotype Section and Point （GSSP）, which is assigned at 6.2m above the base of bed 19 in the Caiziyan section.展开更多
中泥盆世吉维特期至晚泥盆世弗拉期早期,桂林菜子岩剖面处于浅水台地与较深水盆地过渡相区,因而含有较丰富的底栖生物(珊瑚、腕足类等)和浮游生物化石,包括有重要的牙形石带分子,因此该剖面是一重要的浅水相区与较深水相区对比的参考剖...中泥盆世吉维特期至晚泥盆世弗拉期早期,桂林菜子岩剖面处于浅水台地与较深水盆地过渡相区,因而含有较丰富的底栖生物(珊瑚、腕足类等)和浮游生物化石,包括有重要的牙形石带分子,因此该剖面是一重要的浅水相区与较深水相区对比的参考剖面。总体来看,菜子岩剖面的吉维特期晚期较弗拉期早期的四射珊瑚及床板珊瑚均要常见,其中四射珊瑚Truncicarinulum广泛分布,吉维特期晚期(自牙形石Schmidtognathus hermanni带至吉维特期结束)可以称为Truncicarinulum liujingense-Planocoenites guilinensis组合,但其主要特点则是以含有丰富的床板珊瑚为特征。弗拉期早期则以Phacellophyllum的较广分布为特点,可以称为Phacellophyllum stereoseptatum四射珊瑚动物群。文中共描述和图示了5属8种四射珊瑚和9属10种床板珊瑚。其中四射珊瑚有一个新种:Phacellophyllum stereoseptatum Liao and Ma sp.nov.;床板珊瑚有2个新种:Crassialveolites gaoshangtianensis Deng and Ma sp.nov.,Planocoenites guilinensis Deng and Ma sp.nov.。展开更多
The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figur...The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.展开更多
文摘The Givetian-Frasnian boundary at Liujing, Guangxi, South China is for the first time recognized and correlated in high resolution using characteristic chemocycles of element abundance fluctuation integrated with conodont biostratigraphy. The first appearance of Ancyrodella rotundiloba early form is as a biomarker, and the boundary of lowering fluctuation of element abundance followed by a sequence of characteristic chemocycles with a sequence of conodonts is as an abiotic auxiliary marker. The error is not more than 0.10 Ma. The study indicates that in a quiet interval, characteristic chemocycles integrated with biomarkers can be used for boundary recognition and regional correlation in high resolution, and this method has potential for intercontinental
基金supported by the National Natural Science Foundation ofChina(Grants 40472009,40872007,and 40830211)the Major Basic Research Projects of the Ministry ofScience and Technology,China(2006CB806400)
文摘The Caiziyan Middle and Upper Devonian boundary section is located approximately 30 km northeast of Guilin. It hosts relatively abundant benthic and common-rare pelagic fossils, including brachiopods, corals, tentaculites, and conodonts, which may serve as a better suitable section for pelagic and neritic stratigraphic correlation. In this section, 10 ＂standard＂ conodont zones are recognized across the Givetian-Frasnian boundary, including, in descending order, the Lower hassi Zone, punctata Zone, transitans Zone, the Upperfalsiovalis Zone, the Lowerfalsiovalis Zone, disparilis Zone, the Upper hermanni-cristatus Zone, the Lower hermanni-cristatus Zone, the Upper varcus Zone, and the Middle varcus Zone, all of which are defined by the first occurrence of their defining conodont species. The Middle-Upper Devonian （Givetian-Frasnian） boundary is defined by the first occurrence of Ancyrodella pristina in accordance with the Global Stratotype Section and Point （GSSP）, which is assigned at 6.2m above the base of bed 19 in the Caiziyan section.
文摘中泥盆世吉维特期至晚泥盆世弗拉期早期,桂林菜子岩剖面处于浅水台地与较深水盆地过渡相区,因而含有较丰富的底栖生物(珊瑚、腕足类等)和浮游生物化石,包括有重要的牙形石带分子,因此该剖面是一重要的浅水相区与较深水相区对比的参考剖面。总体来看,菜子岩剖面的吉维特期晚期较弗拉期早期的四射珊瑚及床板珊瑚均要常见,其中四射珊瑚Truncicarinulum广泛分布,吉维特期晚期(自牙形石Schmidtognathus hermanni带至吉维特期结束)可以称为Truncicarinulum liujingense-Planocoenites guilinensis组合,但其主要特点则是以含有丰富的床板珊瑚为特征。弗拉期早期则以Phacellophyllum的较广分布为特点,可以称为Phacellophyllum stereoseptatum四射珊瑚动物群。文中共描述和图示了5属8种四射珊瑚和9属10种床板珊瑚。其中四射珊瑚有一个新种:Phacellophyllum stereoseptatum Liao and Ma sp.nov.;床板珊瑚有2个新种:Crassialveolites gaoshangtianensis Deng and Ma sp.nov.,Planocoenites guilinensis Deng and Ma sp.nov.。
基金financially supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2023324)the Hubei Key Laboratory of Paleontology and Geological Environment Evolution,Wuhan Center of China Geological Survey(PEL-202301)+1 种基金the Science and Technology Fundamental Resources Investigation Program(Grand No.2023FY100900)the Natural Science Foundation of China(Grant No.41802018).
文摘The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.
