This paper divides the Telychian into 7 graptolite zones, 12 subzones and 4 chitinoans in the Ziyang region, China. The zones and subzones of England are almost totally suitable for the case of Ziyang in China, though...This paper divides the Telychian into 7 graptolite zones, 12 subzones and 4 chitinoans in the Ziyang region, China. The zones and subzones of England are almost totally suitable for the case of Ziyang in China, though they are 10000 km apart. All the above-mentioned biozones are found only in a unitary continuous section in Ziyang. It has been proved that the Ziyang section is the one with the most complete sequence of Telychian graptolite biozones in the world.展开更多
The El Pintado 1 Silurian section in Seville Province,Spain,described by Loydell et al.(2015),has been ratified by the IUGS as the replacement GSSP for the base of the Telychian Stage,to replace the Cefn Cerig quarry ...The El Pintado 1 Silurian section in Seville Province,Spain,described by Loydell et al.(2015),has been ratified by the IUGS as the replacement GSSP for the base of the Telychian Stage,to replace the Cefn Cerig quarry section in the Llandovery area of Wales,which was found to be within a sedimentary mélange and therefore not a continuous section.No section other than El Pintado 1 has been found to be continuously fossiliferous across the Aeronian/Telychian boundary.展开更多
Marine red beds occur frequently in China through geological time.Despite their complex environments,the red beds are found in three depositional settings:1) oceanic,deep water,as in the Upper Cretaceous of southern T...Marine red beds occur frequently in China through geological time.Despite their complex environments,the red beds are found in three depositional settings:1) oceanic,deep water,as in the Upper Cretaceous of southern Tibet;2) outer shelf,deeper water,as in the Lower-Middle Ordovician of South China;and 3) inner shelf,shallow water,as in the Silurian and Triassic in South China.The Silurian marine red beds are recurrent in the lower Telychian,upper Telychian,and upper Ludlow.This paper is to document the marine nature of the lower Telychian red beds (LRBs) in the Upper Yangtze Region and to discuss the spatial and temporal distribution of the LRBs and their depositional environments.The LRBs are best developed on the north side of the Cathaysian Oldland,which can be interpreted as the source area.It is inferred that they were deposited during a marine regression,characterized by the lack of upwelling,low nutrition and organic productivity with a decrease of biodiversity and a high rate of sedimentation.The iron-rich sediments may have been transported by rivers on the oldland into the Upper Yangtze Sea,as rates of deposition were rapid enough to counteract normal reducing effect around sediment-water interface.The LRBs are different from the off-shore,deeper water red beds of lower Telychian in Avalonia and Baltica and further from the oceanic,deep water red beds of Upper Cretaceous in southern Tibet chiefly in palaeogeographic settings,biotic assemblages and marine environments.展开更多
Study on rugose coral fauna of the Sifengya Formation(early Telychian)and Daluzhai Formation(mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carried out.Rugose coral fauna of the Sifengya Formati...Study on rugose coral fauna of the Sifengya Formation(early Telychian)and Daluzhai Formation(mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carried out.Rugose coral fauna of the Sifengya Formation included 18 genera and 34 species,while Daluzhai Formation with nine genera,ten species.We described rugose coral fauna(12 genera,19 species)including one new genus and five new species,i.e.Protoketophyllum daguanense gen.et sp.nov.,Crassilasma huanggexiense sp.nov.,Pseudophaulactis heae sp.nov.,P.convolutus sp.nov.,and Shensiphyllum minor sp.nov..The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation were analyzed.Particularly,rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper Yangtze region and improve the sequences of early Silurian(Llandovery)rugose coral assemblages in Yangtze region.It is therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch.展开更多
A new genus and species of agnathan Eugaleaspidiformes(Galeaspida), Yongdongaspis littoralis gen. et sp. nov., is described from the Llandovery(lower Silurian) Huixingshao Formation at Yongdong Town, Xiushan County, C...A new genus and species of agnathan Eugaleaspidiformes(Galeaspida), Yongdongaspis littoralis gen. et sp. nov., is described from the Llandovery(lower Silurian) Huixingshao Formation at Yongdong Town, Xiushan County, Chongqing, southwestern China. This new Telychian taxon morphologically exhibits some transitional states between Sinogaleaspidae and a cluster of higher eugaleaspidiforms containing Tridensaspidae, Eugaleaspidae, Yunnanogaleaspis, and Nochelaspis, which we term here as the ’eugaleaspid cluster’. Phylogenetic analysis of an extended character matrix of Galeaspida reveals Yongdongaspis, on which Yongdongaspidae fam. nov. is erected, as the sister taxon of this ’eugaleaspid cluster’, supported by two synapomorphies, the presence of one median transverse canal, and two lateral transverse canals leaving from the infraorbital canal. As the first fish described from the Llandovery Huixingshao Formation in Chongqing, Yongdongaspis provides new fossil evidence for the subdivision and correlation of the Upper Red Beds in South China.展开更多
The age of the Silurian Lower Red Beds in the Upper Yangtze region remains debatable.Twenty-four samples were collected for conodont biostratigraphical studies from the Paiyunan Formation in the Sanbaiti Section,Huayi...The age of the Silurian Lower Red Beds in the Upper Yangtze region remains debatable.Twenty-four samples were collected for conodont biostratigraphical studies from the Paiyunan Formation in the Sanbaiti Section,Huaying,Sichuan Province.The conodont fauna from the Paiyunan Formation,together with the graptolites from the underlying Lungmachi Formation,indicates that the Lower Red Beds at Sanbaiti correspond to the lower Telychian.Comparative analysis indicates that most exposures of the Lower Red Beds in the Upper Yangtze region can be assigned,in general,to the Telychian Stage,except for several localities,where the Lower Red Beds can be roughly dated as an interval between the upper Aeronian and lower Telychian.展开更多
文摘This paper divides the Telychian into 7 graptolite zones, 12 subzones and 4 chitinoans in the Ziyang region, China. The zones and subzones of England are almost totally suitable for the case of Ziyang in China, though they are 10000 km apart. All the above-mentioned biozones are found only in a unitary continuous section in Ziyang. It has been proved that the Ziyang section is the one with the most complete sequence of Telychian graptolite biozones in the world.
基金funded by project PDI2021-125585NB-I00 of the Spanish Ministry of Science,Innovation and Universities‒Agencia Estatal de Investigacion.JF thanks the Grant Agency of the Czech Republic for support of his study(GA23-06198S).
文摘The El Pintado 1 Silurian section in Seville Province,Spain,described by Loydell et al.(2015),has been ratified by the IUGS as the replacement GSSP for the base of the Telychian Stage,to replace the Cefn Cerig quarry section in the Llandovery area of Wales,which was found to be within a sedimentary mélange and therefore not a continuous section.No section other than El Pintado 1 has been found to be continuously fossiliferous across the Aeronian/Telychian boundary.
基金supported by Chinese Academy of Sciences (Grant No. KZCX2-YW-Q05-01)National Basic Research Program of China (Grant No. 2012CB821901)China Geological Survey (Grant No. 1212011120116)
文摘Marine red beds occur frequently in China through geological time.Despite their complex environments,the red beds are found in three depositional settings:1) oceanic,deep water,as in the Upper Cretaceous of southern Tibet;2) outer shelf,deeper water,as in the Lower-Middle Ordovician of South China;and 3) inner shelf,shallow water,as in the Silurian and Triassic in South China.The Silurian marine red beds are recurrent in the lower Telychian,upper Telychian,and upper Ludlow.This paper is to document the marine nature of the lower Telychian red beds (LRBs) in the Upper Yangtze Region and to discuss the spatial and temporal distribution of the LRBs and their depositional environments.The LRBs are best developed on the north side of the Cathaysian Oldland,which can be interpreted as the source area.It is inferred that they were deposited during a marine regression,characterized by the lack of upwelling,low nutrition and organic productivity with a decrease of biodiversity and a high rate of sedimentation.The iron-rich sediments may have been transported by rivers on the oldland into the Upper Yangtze Sea,as rates of deposition were rapid enough to counteract normal reducing effect around sediment-water interface.The LRBs are different from the off-shore,deeper water red beds of lower Telychian in Avalonia and Baltica and further from the oceanic,deep water red beds of Upper Cretaceous in southern Tibet chiefly in palaeogeographic settings,biotic assemblages and marine environments.
文摘Study on rugose coral fauna of the Sifengya Formation(early Telychian)and Daluzhai Formation(mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carried out.Rugose coral fauna of the Sifengya Formation included 18 genera and 34 species,while Daluzhai Formation with nine genera,ten species.We described rugose coral fauna(12 genera,19 species)including one new genus and five new species,i.e.Protoketophyllum daguanense gen.et sp.nov.,Crassilasma huanggexiense sp.nov.,Pseudophaulactis heae sp.nov.,P.convolutus sp.nov.,and Shensiphyllum minor sp.nov..The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation were analyzed.Particularly,rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper Yangtze region and improve the sequences of early Silurian(Llandovery)rugose coral assemblages in Yangtze region.It is therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDA19050102 and XDB26000000)the National Natural Science Foundation of China(Grant No.41872023)+1 种基金the Key Research Program of Frontier Sciences,CAS(Grant No.QYZDJ-SSW-DQC002)the Mineral Resources Protection and Supervision Project:Evaluation and Survey of the Silurian Fish Fossil Resources of Youxiu Fold Belt,Chongqing。
文摘A new genus and species of agnathan Eugaleaspidiformes(Galeaspida), Yongdongaspis littoralis gen. et sp. nov., is described from the Llandovery(lower Silurian) Huixingshao Formation at Yongdong Town, Xiushan County, Chongqing, southwestern China. This new Telychian taxon morphologically exhibits some transitional states between Sinogaleaspidae and a cluster of higher eugaleaspidiforms containing Tridensaspidae, Eugaleaspidae, Yunnanogaleaspis, and Nochelaspis, which we term here as the ’eugaleaspid cluster’. Phylogenetic analysis of an extended character matrix of Galeaspida reveals Yongdongaspis, on which Yongdongaspidae fam. nov. is erected, as the sister taxon of this ’eugaleaspid cluster’, supported by two synapomorphies, the presence of one median transverse canal, and two lateral transverse canals leaving from the infraorbital canal. As the first fish described from the Llandovery Huixingshao Formation in Chongqing, Yongdongaspis provides new fossil evidence for the subdivision and correlation of the Upper Red Beds in South China.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB26000000)the National Science and Technology Major Project of China(No.2017ZX05035002-001)+1 种基金the National Natural Science Foundation of China(Nos.41972162 and 41725007)the Estonian Research Council(No.PRG836)。
文摘The age of the Silurian Lower Red Beds in the Upper Yangtze region remains debatable.Twenty-four samples were collected for conodont biostratigraphical studies from the Paiyunan Formation in the Sanbaiti Section,Huaying,Sichuan Province.The conodont fauna from the Paiyunan Formation,together with the graptolites from the underlying Lungmachi Formation,indicates that the Lower Red Beds at Sanbaiti correspond to the lower Telychian.Comparative analysis indicates that most exposures of the Lower Red Beds in the Upper Yangtze region can be assigned,in general,to the Telychian Stage,except for several localities,where the Lower Red Beds can be roughly dated as an interval between the upper Aeronian and lower Telychian.